The game will provide both clubs with an opportunity to progress to the semi-finals of the competition at Hampden and the Rangers boss knows his side will have to be at their best to beat Callum Davidson's men, who have already won the League Cup this season.
Gerrard, however, hopes his players can get back to the levels they produced against Celtic in the Cup last weekend following Wednesday night's 1-1 draw with the Saints at McDiarmid Park.
On the big match coming up, he said: "It's difficult to predict how the game is going to pan out but I'm hoping to see more intensity and more quality from our point of view.
"I think it goes without saying the team will look different [from Wednesday], our game plan will look different and it's a fresh game, but a game we are very much looking forward to.
"St Johnstone are a good team. They will be organised, well drilled and they are having a fantastic season themselves, so it is all to play for at the weekend.
"I said a few weeks ago that once the league was wrapped up our priority becomes the Scottish Cup. You obviously have to see all the league games out and we want to try and remain unbeaten, so we picked a team to try and win on Wednesday.
"We obviously never saw the closing moments out in the right way and we were punished. It was a fair result but we are glad that is out the way and we've come through with no injuries or any scares.
"We are in a good place now going into the weekend and I want the performance to look very much different.
"The team will look different because I made a lot of changes in midweek and I made substitutions on the back of what that game needed, with one eye on this weekend. So we're excited and in a good place going into this.
"We want to show St Johnstone big respect. They have already won a cup themselves and are in the top six. But if we play close to our best, like we did in the last performance at Ibrox against Celtic, we should have enough to get the job done."
When asked if attacker Scott Wright could again start on Sunday after he impressed and scored Rangers' goal in Perth on Wednesday, the manager - speaking at his pre-match press conference - responded: "Scott has done everything he's been asked to do whether that be in the gym, whether it be to do with his diet or on the training pitch. And certainly in games in terms of taking information on board he's been a model professional.
"I think he has shown real good impact from the bench so far. One of the games he started against Cove I think he might have got man of the match, so again it was strong performance.
"The other night in flashes he showed the reason why we tried to bring him in here. He's exciting, he's quick, he can create and he can score. He's one that is a work in progress but we are very excited to have him here and he's certainly pushing for a starting place at the weekend."
With first-team players Nathan Patterson, Bongani Zungu and Calvin Bassey now suspended after the SFA's decision to stand by their six-match bans for the trio, the return to fitness of captain James Tavernier has come at a good time for the Light Blues.
Gerrard added: "It's a big boost and I think you can tell from his smile and the way he is around the training pitch today.
"He's a little bit stiff and tired from the game on Wednesday as it was his first hour in many weeks, but he's come through with no issues in terms of the injury which is the biggest boost I needed.
"He'll obviously play at the weekend again with Nathan not available now, so we are all delighted to have him back.
"He's big for us and his contribution this season has been mega. He's got a massive part to play from now until the end of the season."
MATCH HUB: You can follow all pre-match build-up and live coverage of the game HERE.
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