Malik Tillman scored his second goal within five days
Rangers secured a third consecutive Scottish Premiership win of the season with a comfortable dismissal of St Johnstone.
Striker Theo Bair squandered a good early chance for the visitors.
But their threat diminished after Malik Tillman replicated his midweek scoring leap to head in off the bar.
Striker Antonio Colak grabbed his third goal in three games with a clinical finish before late strikes from Scott Arfield and Tom Lawrence.
Rangers' seventh straight home win since losing to Celtic in April is the perfect boost for manager Giovanni van Bronckhorst ahead of Tuesday's Champions League play-off first leg against PSV Eindhoven at Ibrox.
Both sides took to the Ibrox sunshine on the back of impressive wins - Rangers having turned around a two-goal deficit against Union Saint-Gilloise, and Saints away to Motherwell last weekend.
It was Callum Davidson's unchanged side who fashioned the better chances on the break in the early stages despite losing Cammy MacPherson in the opening minutes, the injury forcing an early debut for former Watford midfielder Daniel Phillips following his midweek signing.
Bair should have done better than poke wide from five yards after a cross from former Rangers winger Jamie Murphy fell kindly for the striker.
However, when John Lundstram won a corner off the palms of goalkeeper Remi Matthews with a powerful drive, James Tavernier's cross found Tillman ghosting in at the back post to head in off the underside of the crossbar.
The on-loan Bayern Munich midfielder's second goal in five days was similar to his impressive, match-winning leap against the Belgians on Tuesday.
Winger Rabbi Matondo sent a vicious drive off the crossbar before setting up the next two goals.
His block as Drey Wright dallied on an attempted clearance handed Colak his chance, before he then rounded Matthews to set up Arfield for a tap-in.
There was still time for Arfield to set up follow midfield substitute Lawrence for his first Rangers goal.
Man of the match - John Lundstram (Rangers)
There were a few contenders - Scott Wright and Rabbi Matondo in particular - but it was John Lundstram (left) who drove Rangers forward from midfield when Saints were proving stubborn early on
Rangers benefit from stronger squad
The game appeared to be following a similar pattern to Rangers' opening two victories over Livingston and Kilmarnock, with Van Bronckhorst's side labouring to break down a packed defence.
However, once they got their noses in front, the Ibrox side were a different animal.
Van Bronckhorst made four changes, with winger Ryan Kent and defender James Sands missing through injury and illness respectively, and the way they finished with a flourish with two substitutes finding the net showed Rangers' added strength in depth this season.
In summer signing Antonio Colak, in particular, they have found the goal poacher they needed with Alfredo Morelos still viewed short of match fitness following injury.
St Johnstone will look to that early miss - and there were suggestions of offside in Colak's goal - as Davidson quickly consigns the experience to history.
Considering they have beaten Rangers only once in 15 meetings and have lost the latest four, anything taken from Ibrox would have been a bonus.
What they said
Rangers manager Giovanni van Bronckhorst: "I expect Ryan Kent and James Sands to be okay for Tuesday.
"Really pleased because we changed some players today - some we had to and some we gave more minutes - so overall it was a positive day for us. I'm pleased with the overall display, the three points are obviously important, the four goals, a clean sheet and the drive to keep going and try to score goals right to the end."
St Johnstone manager Callum Davidson: "First half, I thought we played well. Rangers had the majority of the ball, but we defended well as a group and worked extremely hard and at times when we transitioned to the other end was quite good.
"Second half, we tried to have a little go and put bodies forward to put them under a bit of pressure. I'm disappointed with the goals conceded, but I have seen big improvements in the team going forward."
What's next?
Rangers host PSV Eindhoven in Tuesday's Champions League play-off first leg (20:00 BST) before visiting Hibernian in the Premiership on Saturday (12:30) as St Johnstone host Aberdeen (15:00).
