St Johnstone were unable to take advantage of the few chances that came their way and were punished at Ibrox.
A first half opener from Malik Tillman was followed after the break by finishes from Antonio Colak, Scott Arfield and Tom Lawrence as Rangers picked up a comfortable three points on home soil.
Perth boss Callum Davidson was afforded the opportunity to name the same starting line-up that dramatically defeated Motherwell 2-1 last weekend.
Melker Hallberg again had the captain’s armband with usual skipper Liam Gordon having to settle for a spot on the bench.
Alex Mitchell, on loan from Millwall, retained his position in the heart of a central defensive three. He has been a standout performer since arriving.
There was, however, a scare for him on four minutes when his short back pass to Remi Matthews created a sense of panic. The goalkeeper’s kick struck Tillman and went behind for a goal-kick.
An early change was required when Cammy MacPherson hit the turf in the opening 10 minutes and his replacement resulted in a club debut.
Daniel Phillips, who signed a two-year deal during the week, was called from the bench to take his place in the middle of the park.
The Trinidad and Tobago international quickly showed off a couple of neat touches and passes, but would realise he would be in for a busy afternoon.
Rangers, as expected, had the majority of the ball but a quick Jamie Murphy break was soon a promising sight.
He slipped the ball to Graham Carey who, 25 yards out, went for glory with a left-footed strike. It was straight at Jon McLaughlin.
On 16 minutes, another chance when Murphy’s cross fell for Theo Bair deep inside the box.
The Canadian forward, despite being on the deck, connected sweetly but the ball fizzed by the post. He should’ve scored.
Due to the heat - temperatures were hovering in the mid-twenties - there was a water break on 23 minutes.
That didn’t throw the concentration of shot-stopper Matthews who, on the half hour mark, pulled off a smart diving stop to deny John Lundstram’s powerful hit.
Moments later, though, Rangers had the lead when James Tavernier clipped to the back post where Tillman said thank you very much and nodded in off the underside of the crossbar.
While trailing at the break, Saints had actually looked reasonably solid and Davidson would be pleased with certain aspects of the performance.
He wouldn’t have been pleased with the time Rabbi Matondo was given after the restart to line-up a strike and smash the upright.
Rangers went close again when Borna Barisic tried his luck with a free-kick from the edge of the box which flew marginally over and brushed the roof of the net.
The hosts doubled their advantage with 61 minutes played and Saints were the masters of their own downfall.
Drey Wright was caught in possession inside his own box, the ball broke for Colak and the striker fired low into the back of the net.
Fresh legs were introduced as the half progressed with Stevie May, James Brown, Ali Crawford and Michael O’Halloran all utilised.
Saints were on the hunt for a way back into the game but, instead, Rangers added a third in the 80th minute thanks to substitute Arfield.
And then a fourth moments later from Tom Lawrence. It was all too easy.