On Saturday, Rangers bounced back from their League Cup loss to St. Mirren by beating Motherwell 3-1 at Ibrox.
Steven Gerrard's men went behind to a Callum Lang goal in the first half, but a Kemar Roofe brace late in the second half and a goal from Cedric Itten ensured that they won the game.
With that win, Rangers hit 50 points in the league, with only 18 games played so far. They are 16 points ahead of Celtic, with their Glasgow rivals having three games in hand.
Gerrard's side last dropped points in the league in September, when they drew 2-2 away at Hibernian. Since then, they have won 10 league games in a row. Rangers are in pole position to finally break Celtic's dominance in the Scottish Premier League, and hand Gerrard his first league title as manager.
St. Johnstone are in 10th position in the table and have not won a league game since early November. On Saturday, they lost 3-2 to St. Mirren and also had Jason Kerr sent off.
St. Johnstone vs Rangers Head-to-Head
Rangers have won 26 of the last 39 games that they have played against St. Johnstone, losing only five times against Wednesday's opponents. These two teams have had eight draws against each other.
St. Johnstone form guide: L-W-L-D-W
Rangers form guide: W-L-W-W-W
St. Johnstone vs Rangers team news
Jason Kerr is suspended after he was shown a red card in the game against St. Mirren on Saturday. He is likely to be replaced by Shaun Rooney.
St. Johnstone don't have any other known concerns regarding player unavailability.
Suspended: Jason Kerr
Ryan Jack still hasn't shrugged off a muscle problem, while Nikola Katic is a long-term absentee.
Leon Balogun missed the game against Motherwell with a head injury, and is a doubt for this game as well.
Alfredo Morelos is back from suspension, after missing two games following a sanction for violent conduct in the game against Dundee United a couple of weeks ago.
Jordan Jones and George Edmundson are not available until the game against St. Mirren on 30 December, after they were banned for breaching COVID protocols earlier this season.
Leon Balogun suffered a head injury against Dundee United last week, and will not start this game.
Injured: Nikola Katic, Ryan Jack
Doubtful: Leon Balogun
Suspended: Jordan Jones, George Edmundson
St. Johnstone vs Rangers Predicted XI
St. Johnstone Predicted XI (3-4-2-1): Zander Clark; Shaun Rooney, Liam Gordon, Jamie McCart; Danny McNamara, Ali McCann, Murray Davidson, Scott Tanser; David Wotherspoon, Craig Conway; Stevie May
Rangers Predicted XI (4-3-3): Allan McGregor; James Tavernier, Connor Goldson, Filip Helander, Borna Barisic; Steven Davis, Joe Aribo, Scott Arfield; Ryan Kent, Alfredo Morelos, Kemar Roofe
St. Johnstone vs Rangers Prediction
St. Johnstone, on paper at least, should not come close to challenging Rangers in this game.
With Morelos returning, we are predicting that Rangers will stroll to a comfortable win in this game.
Prediction: St. Johnstone 0-3 RangersPublished 22 Dec 2020, 13:24 IST