Ireland internationals Stuart McCloskey and Nick Timoney missed the win in Italy, but Ulster hope both will be available for selection to face the Bulls, who are coming off a 56-20 Champions Cup win over Stade Francais.
Forward Ben Donnell, back-three player Ethan McIlroy and second row Eli Snyman will be monitored throughout the week after resuming training.
Ulster are still without Eduardo Bello, Iain Henderson, Rob Herring, James Hume, Charlie Irvine, Aitzol Arenzana-King, Stewart Moore, Jude Postlethwaite, Callum Reid and Bryn Ward.
Richie Murphy's side face the Bulls at Loftus Versfeld Stadium (12:45 BST) before travelling to Cape Town, where they will take on the Stormers on 31 October (12:45 GMT).
Ulster sit 11th in the URC table after two draws and a defeat from their opening three games.
The Bulls, beaten finalists last season, and Stormers lie third and fourth in the standings having both won two out of three.
Ulster beat the Bulls 28-7 in Belfast last season and drew 38-38 with the Stormers. Last year's South African trip yielded a 34-26 win over the Sharks in Durban and 49-31 defeat by the Lions in Johannesburg.
Ulster quartet doubts for Zebre as Snyman ruled outpublished at 12:24 BST 13 October
12:24 BST 13 October
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Image caption,
Snyman will not be available this week because of concussion
Four players have emerged as doubts for Ulster's Challenge Cup opener against Zebre in Parma on Saturday.
Prop Eduardo Bell, who did not feature in Saturday's United Rugby Championship draw with Munster, may not be risked after picking up a hamstring injury in training.
Second row Ben Donnell, full-back Ethan McIlroy and hooker Tom Stewart all sustained unspecified knocks in the Munster game.
Eli Snyman, who started alongside Donnell at lock on Saturday, is ruled out with a concussion.
On a more positive note, full-back Michael Lowry has returned to full team training after suffering a concussion in the opening URC loss to Edinburgh on 25 September.
After a defeat and two draws in the URC, Ulster are hunting a first win of the season against Zebre before travelling to South Africa for league games against the Bulls and Stormers.
Ulster need 'honest conversations' after winless startpublished at 08:37 BST 11 October
08:37 BST 11 October
Image source, Inpho
Image caption,
Tom Stewart captained Ulster in Saturday's thrilling draw with Irish rivals Munster
Ulster hooker Tom Stewart admits "I don't think I've come to the party well enough" and says the squad must have "honest conversations" after an underwhelming start to the season.
Successive draws with Glasgow and Munster after a loss to Edinburgh leaves Ulster winless in the United Rugby Championship before starting their Challenge Cup campaign away to Zebre next week.
Head coach Richie Murphy said he was "bitterly disappointed" after his side were forced to fight back for a 26-26 draw with Munster, while Stewart questioned his own contributions to the game in Belfast.
"From a personal point of view, I'm not happy with my performances about it. I don't think I've come to the party well enough, I don't know if it's my preparation or the mental side to the game," said Stewart, who captained Ulster against Glasgow and Munster in the injured Iain Henderson's absence.
"It's something I really need to have a look at and plan better or whatever it is, but I need to start understanding why that is the case."
Stewart, who marked his seventh Ireland cap with a try against Japan over the summer, added: "From my own point of view, I need to properly watch back my intent in some of the collisions and my actual process around what I'm doing.
"Then I think we need to have some honest conversations this week within ourselves, with the team, players and coaches to see where we're at."
Ulster travel to Zebre on Saturday (15:15 BST) before travelling to South Africa for difficult URC assignments against the Bulls and Stormers.
For Stewart, Ulster "can't shy away" from the shortcomings in their performances as they strive to kick-start their season.
"It's hard, when you have a game like that you don't want to watch it back," added the 25-year-old.
"You don't want to review yourself properly, you don't want to look at the hard stuff, the nitty-gritty that you haven't done well, but that's where you find the fixes, the learnings.
"The hardest stuff you watch will be the most impactful stuff going forward."
Seven Ulster changes as Beirne makes Munster returnpublished at 14:56 BST 8 October
14:56 BST 8 October
Matt Gault BBC Sport NI senior journalist
Image source, Getty Images
Image caption,
Stuart McCloskey starts at centre for Ulster while Tadhg Beirne returns to the Munster pack
Ulster head coach Richie Murphy has made seven changes for Saturday's United Rugby Championship game against Munster, with returning Ireland internationals Stuart McCloskey and Nick Timoney included in the starting line-up.
McCloskey, who started all three of Ireland's Nations Championship matches in July, returns at inside centre for the Affidea Stadium contest (17:30 BST), forming a new midfield partnership with summer signing Jamie Benson.
It will be 34-year-old McCloskey's 218th Ulster appearance, moving him alongside former captain Rory Best in joint-third on the province's all-time cap list.
Timoney returns to the back row alongside Ireland team-mate Cormac Izuchukwu, who shifts back from the second row, and Juarno Augustus, while recent recruits Ben Donnell and Eli Snyman form a new second row.
The front row of Eric O'Sullivan, captain Tom Stewart and Keynan Knox is unchanged.
Nathan Doak makes his first start of the season at scrum-half, with Jack Murphy retained at 10 following a try-scoring display in last week's 33-33 draw with Glasgow.
Jacob Stockdale will make his 150th appearance on the left wing a week later than planned after being forced to withdraw from the Glasgow game through injury. Zac Ward, who started in the 11 jersey last week, is not involved.
Robert Baloucoune returns on the right wing after missing the trip to Scotstoun because of concussion, while Ethan McIlroy is retained at full-back.
Henry Walker, returning Ireland international Tom O'Toole, Tom McAllister, James McNabney and David McCann provide forward cover on the bench, while Matthew Devine, Jake Flannery and Chay Mullins are the backline replacements.
Image source, Getty Images
Image caption,
Young fly-half Charlie O'Shea (left) is on the Munster bench while back row Gavin Coombes returns to the starting XV
Munster, who earned an impressive bonus-point win over the Bulls last weekend, are boosted by captain Tadhg Beirne's return from injury.
Having missed the end of last season through injury before featuring for Ireland over the summer, British and Irish Lions second row Beirne returns as one of nine changes made by head coach Clayton McMillan.
Props Jeremy Loughman and Kieran Brookes return to join Marnus van der Merwe in the front row, while Jack O'Donoghue, Alex Kendellen and Gavin Coombes form an entirely changed back row.
Ben O'Connor and Alex Nankivell return at full-back and outside centre respectively, while JJ Hanrahan is reinstalled at fly-half.
Charlie O'Shea, 20, is named among the replacements after starring on his first against the Bulls last week.
"JJ Hanrahan was excellent against Glasgow in round one and I was really impressed with how he managed the end game against Bulls last week," said McMillan.
"It has been a whirlwind for Charlie O'Shea, it's hard to believe that it's less than two months since he pitched up with us. He hasn't missed a beat and gets another opportunity this weekend as a replacement."
Munster ran out resounding 41-14 winners when the provinces last met at Thomond Park in April, while Ulster won 28-3 in the last meeting in Belfast on New Year's Day.
Ulster 'need to put together 80 minutes' - Timoneypublished at 10:27 BST 7 October
10:27 BST 7 October
Richard Petrie BBC Sport NI Journalist
Image source, Inpho
Image caption,
Ireland back row Timoney has yet to play for Ulster this season
Nick Timoney says Ulster "need to put 80 minutes together" against Munster on Saturday to try and secure their first victory of the United Rugby Championship season.
The Irish province suffered an opening weekend defeat to Edinburgh in Belfast and then drew with Glasgow in a dramatic encounter at Scotstoun.
The Ireland back row sat out both games but is raring to go for this weekend's interprovincial meeting at the Affidea Stadium.
"Lots of glimpses of amazing rugby we have been playing, and lots of impressive performances, we just haven't probably put it together for 80 minutes just yet," Timoney said of Ulster's first two games of the new campaign.
"The Glasgow game was closer to that but we probably left a couple of chances out there to try and win the game. It felt like an improvement from the week before.
"We're striving to get better in a lot of areas and bits of that are coming through.
"It's just about putting it together for 80 minutes on the pitch and if we can do that we will be in a good place."
The Ulster forward added that the squad are keen to make up for the disappointment of last season when they finished outside the top eight in the URC and went down heavily to Montpellier in the Challenge Cup final.
"Last season tailed off a bit and didn't end the way we wanted it to and we just want to rectify that really and I want do the best I can for the team.
"It starts with being the best individual rugby player I can be."
Timoney knows the visiting Munster team will pose a significant challenge.
"There's an intensity to them [interpros] that's a little bit different. We know them a bit better and they know us a bit better than the other teams.
"When this place gets rocking, there is no better atmosphere and there is no better team than Munster to play in that context."
Ward ruled out of Munster game but trio returnpublished at 16:01 BST 6 October
16:01 BST 6 October
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Image caption,
Bryn Ward was injured in Ulster's defeat by Glasgow Warriors
Ulster back row Bryn Ward has been ruled out of Saturday's United Rugby Championship game against Munster because of a knee injury.
Ward sustained the problem in last weekend's dramatic 33-33 draw with Glasgow Warriors at Scotstoun.
Scrum-half Matthew Devine is a doubt for the interprovincial encounter at the Affidea Stadium, which has a 17:30 BST kick-off.
The former Connacht player is carrying a shoulder injury and his fitness for selection will be assessed later this week.
On a more positive note for Ulster head coach Richie Murphy, Jacob Stockdale has returned to full training after overcoming the hip injury which forced him to withdraw from the starting line-up for the meeting with Glasgow.
Similarly, Scott Wilson (ankle) and Robert Baloucoune (concussion) have are both fit for selection after injuries.
For Munster, Diarmuid Kilgallen (hamstring), Michael Milne (ankle) and Fineen Wycherley (shoulder) are all unavailable.
Kilgallen and Milne both left the field during the first half of the win over the Bulls, while Wycherley was a late withdrawal before the game.
Brian Gleeson and John Hodnett both passed HIAs on Saturday and are available for selection.
Diarmuid Barron, Jack O'Donoghue and Alex Nankivell are completing the return-to-play protocols.
Ulster are still aiming to secure their first URC win of the season after an opening weekend defeat by Edinburgh in Belfast was followed by a draw in Glasgow.
Munster beat the Bulls in Limerick on Saturday after losing to Glasgow Warriors at Thomond Park seven days earlier.
Stockdale in line for 150th Ulster appearance published at 14:48 BST 1 October
14:48 BST 1 October
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Image caption,
Stockdale is one of four Ireland internationals to return to the Ulster team
Jacob Stockdale is in line to make his 150th apperance for Ulster in Saturday's United Rugby Championship match against Glasgow Warriors in Scotstoun (17:30 BST).
Stockdale is one of four Ireland internationals who return to the starting line-up from last week's defeat by Edinburgh in Belfast.
Tom Stewart, Cormac Izuchukwu and Bryn Ward are all named in the side, while new signings Keynan Knox, Matthew Devine and Chay Mullins are set to make their first starts.
Stewart and Knox come into the front row to join Eric O'Sullivan, while Izuchukwu comes into the second row where he will partner Eli Snyman.
In the back row, Bryn Ward comes in for his season bow at number eight with last week's player of the match David McCann switching to open-side flanker and academy player James McKillop at blind-side.
Jack Murphy retains his place at fly-half, but will be partnered by Devine, who starts for the first time having made his debut off the bench last week.
In midfield, Jamie Benson retains his place at inside centre but will be partnered this week by Ethan McIlroy at outside, while it is all change in the back three.
Michael Lowry and Robert Baloucoune suffered concussions against Edinburgh, with Stockdale in at full-back and former Connacht player Mullins in at right-wing, while Zac Ward comes in for his first start of the campaign on the left.
Nathan Doak and Juarno Augustus have been deemed fit for a place on the bench that has a 6-2 split.
Ulster: Stockdale; Mullins, McIlroy, Benson, Z Ward; Murphy, Devine; O'Sullivan, Stewart, Knox; Izuchukwu, Snyman; McKillop, McCann, B Ward.
Ulster without trio of backs for Glasgow contestpublished at 15:47 BST 29 September
15:47 BST 29 September
Richard Petrie BBC Sport NI Journalist
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Image caption,
Michael Lowry, Aitzol Arenzana-King and Robert Baloucoune will miss the encounter with Glasgow
Ulster will be without backs Michael Lowry, Aitzol Arenzana-King and Robert Baloucoune for Saturday's United Rugby Championship game against Glasgow at Scotstoun (17:30 BST).
Full-back Lowry and wing Baloucoune suffered concussions in the Irish province's 34-29 defeat by Edinburgh in their opening URC game of the 2026-27 campaign.
Winger Arenzana-King picked up a knee injury during the game in Belfast, from which Ulster emerged with two bonus points.
All three players started last weekend's fixture, with Lowry captaining the side and scoring the first of Ulster's four tries in a match which Richie Murphy's side's comeback fall short after they bounced back from a 34-5 deficit.
Glasgow began their season with an impressive 26-20 victory on the road at Munster.
"Everyone was really disappointed with how we played at the weekend but I think the glimpse of 20 minutes of really good rugby was what we were expecting to bring," Ulster head coach Richie Murphy told BBC Sport NI's Mark Sidebottom.
"Yesterday we started our review and the things that we got wrong. We know we are a lot better than that we produced at the weekend.
"This week we have a really tough assignment away to Glasgow but it's really important that we turn the page here and try and right some of the wrongs that were in that game.
"Starting with getting our breakdown right, getting our defensive line coming forward and making sure we're connected. You've got to be at your best to get anything over there."
Image source, Inpho
