The Scotland international and his Hoops team-mates were unable to prevent Kilmarnock romping to a historic 2-0 win in an SPL on Saturday.
Incredibly, it was the Rugby Park club's first victory at Parkhead since 1955. But the midfielder is glad Neil Lennon's team have a League Cup game with Saints at home tomorrow night.
And he reckons Celtic, who received widespread plaudits for their performance against Barcelona in Spain last Tuesday, can get the loss out of their system with a triumph.
He said: "When you are on a bit of roll you can't wait for the next game. But the same is true when you have a bad game like we did on Saturday.
"I think our desire to win the game and our work-rate will be the No.1 topic of conversation, rather than our technical ability, today and tomorrow.
"The loss to Kilmarnock on Saturday was nothing to do with how we passed the ball or shot at goal. It was down to a simple desire to win the match.
"Kilmarnock showed an abundance of that and we didn't. We can't wait to get back out there and rectify it."
Commons, though, feels Celtic will have to be far more clinical up front against an on-form St. Johnstone team than they were against Kilmarnock to win their quarter-final showdown.
He said: "We had good chances. Joe Ledley missed a good chance in the first half and Tony Watt and Gary Hooper should have scored in the second half.
"We certainly created chances at the weekend. But we never looked like we put their keeper under any sort of pressure. He had hardly any saves to make.
"At a club like Celtic you are expected to work their keeper for the full 90 minutes. It is required of you here to do that."
Meanwhile, Commons has urged teenager striker Watt, who missed an absolute sitter with an empty net beckoning after coming on in the second half, not to let his gaffe play on his mind.
He said: "He has to realise it is just one of those things that happens some time. Joe, who is an experienced international, missed an open goal as well in the first half.
"It was a freak performance and result."