The 27-year-old who was cut from his job as a backup quarterback by the Edmonton Eskimos in July put up an unlikely 8-2 record since taking over as the Montreal Alouettes' starter in August.
His numbers were so-so and he was hardly dazzling behind centre, but the Asheville, N.C. native earned enough wins for the Alouettes to turn a 1-7 record into a 9-9 mark and claim second place in the East Division.
He will get his first playoff start Sunday when the Alouettes play host to the crossover B.C. Lions in the East Division semifinal at Percival Molson Stadium.
"I don't think I'm trying to prove anything to myself," Crompton said Friday. "We're out here as a team, trying to make sure we execute our game plan."
Crompton is not at the point where he says a lot to the media. But neither did Anthony Calvillo when he first became the Montreal starter in 2000, before he went on to win three Grey Cups and set the league's all-time passing record before he retired after the 2013 season.
Finding a replacement for Calvillo was a nightmare early in the campaign, as his designated successor Troy Smith struggled to find receivers, then got injured and then was let go.
The experienced Alex Brink didn't do much better, and Tanner Marsh didn't get much action other than running the ball on short yardage plays.
Then along came Crompton, who looked good in his first appearance in relief of Brink in a loss at Winnipeg on Aug. 22.
He took over as the starter the next week against Ottawa and the team went on a roll. It helped that the Alouettes had made an in-season coaching change that brought in former CFL and NFL star Jeff Garcia to handle the quarterbacks.
Thanks mostly to remarkable play by the defence, the Alouettes won games even though Crompton did not have a single game with 300 yards passing.
The Alouettes had won six in a row before a regular season-ending loss in bad weather in Hamilton last week in which he passed for a season high 284 yards.
Now, Crompton gets his first test in a win-or-go-home game.
"I expect him to handle it like he's handled most of the games he's started, which has been pretty good," said general manager Jim Popp. "He's that type of guy.
"He'll go with the flow. Hopefully we can just manage the game, take care of the ball and give us a chance."
He has done that. Crompton threw 11 touchdown passes while being picked off only eight times.
After the team's early season quarterback woes, all-star tackle Josh Bourke is glad to have a pivot that gets the job done.
"I think he'd admit he's still a work in progress, along with our whole offence," said Bourke. "He has a calm demeanour. He's very confident and he commands the huddle well.
"The good thing is we don't need him to throw for 500 yards. He doesn't have to be A.C. because of how good the defence is. That's the good news. We don't need five touchdown passes, just take care of the ball, don't turn it over and score when we have short fields. That's what he's been able to do."
Crompton has developed chemistry with Montreal's top receiver Duran Carter, whose used a second half surge to finish third in the league with 75 catches for 1,030 yards. But he has other weapons in S.J. Green and Brandon London he can use more.
"Everybody has big play ability for us," said Crompton. "S.J. with the deep ball threat, Duran who breaks a tackle and he's gone, Brandon with the jump ball ability.
"We've got to get them the ball and let them work in space. I think we've done a good job of that this week in practice. Now's the time to put it to the test."
It was unclear who will carry the ball. Brandon Whitaker remains on the six-game injured list, while Tyrell Sutton is battling an ankle injury. Sutton didn't practise this week and, for the first time, coach Tom Higgins admitted he may not play. Brandon Rutley may be called in off the practice roster, and they also have Chris Rainey on hand.
Kick returner James Rodgers also looks doubtful, although defensive back Geoff Tisdale has practised and should return from a concussion.