The England flanker was one of the stars of the Lions' tour of South Africa four years ago.
But with fierce competition in the tourists' back-row, Croft is under no illusions that the Patersons Stadium clash could be crucial.
"You may only get one chance to play, and you have got to take it," said Croft.
"If you come off the pitch with regrets, you have only yourself to blame.
"These are the last few games of the season and you have got to go all out and hope you do enough to win a Test place.
"It could be your last game if you don't perform. You have to go out and give everything left in the tank. There is no point holding anything back."
Croft's return to a Lions jersey marks a remarkable journey since he fractured a vertebrae in April 2012.
He made his comeback in January and quickly got back to his best form to help Leicester to the Premiership crown - something the Lions selectors could not ignore.
"He's a special player is Tom," said forwards coach Graham Rowntree. "He has done exceptionally well to come back from a nasty injury.
"We couldn't ignore his form as England selectors, and those performances have got him on the plane for this trip.
"He has got good competition. 'Lyds' [Dan Lydiate] played very well on Saturday, so the challenge is there for Tom, and we've got other guys in the back row that can play six as well."