The visitors make the trip to Glasgow after a 10-day break due to two Aberdeen players having tested positive for coronavirus last week.
While Steven Gerrard would have wanted Rangers to progress further in the Europa League, the defeat to Bayer Leverkusen could prove to be a blessing in disguise for the Glasgow giants.
Sunday's convincing victory over St Mirren has resulted in last season's runners-up establishing an early two-point advantage over fierce rivals Celtic.
Although the margin is largely irrelevant at this stage of the campaign, Gerrard will welcome the club sitting ahead of the reigning champions at a time when there remains uncertainty over the future of Alfredo Morelos.
The ongoing saga has the potential to cause distractions, but the in-demand Colombian bagged himself a double at the weekend to suggest that positive talks have been held behind the scenes.
Despite there being an air of inevitability about a departure, Gerrard will want his star man to continue to perform until recent addition Kemar Roofe is ready to take his spot in the starting lineup.
As far as St Johnstone are concerned, they will be delighted to get back onto the pitch after seeing Saturday's encounter with Aberdeen postponed with 24 hours' notice.
Given the desire for his players to improve their match fitness as soon as possible, Callum Davidson would have been left frustrated with the unforeseen break from action.
Nevertheless, the Saints now face three games in just over a week, and there is a window of opportunity for the team to build some momentum.
While they only recorded a 1-1 draw at Dundee United on the first weekend of the season, the share of the spoils came after playing half of the contest at a man disadvantage.
Rangers Scottish Premiership form: WW
Rangers form (all competitions): WLW
St Johnstone Scottish Premiership form: D
Goalkeeper Allan McGregor is expected to be available after a knock kept him out of Sunday's fixture.
Roofe and the previously-injured Jermain Defoe are only just resuming first-team training, meaning that it is unlikely that either player will feature.
St Johnstone will be without Michael O'Halloran, who serves his one-match ban for two yellow cards picked up on the first weekend of the season.
Stevie May could be brought into the starting lineup.
Rangers possible starting lineup:
McGregor; Tavernier, Goldson, Balogun, Barisic; Davis, Kamara; Arfield, Hagi, Kent; Morelos
St Johnstone possible starting lineup:
Parish; Kerr, Gordon, McCart; McNamara, McCann, Craig, Booth; May, Hendry, Wotherspoon
We say: Rangers 2-0 St Johnstone
With the Rangers squad having played two more competitive games than their next opponents, it would come as a surprise if they did not run out comfortable winners. Although St Johnstone impressed against Dundee United on the opening weekend, they may be slightly off the pace on Wednesday night.