They are at polar ends on the depth chart and, probably, in the hearts of Argonauts' fans: Damon Allen and Mike McMahon.
Tonight, in the team's final pre-season game in Montreal, both face scrutiny that could define where they go in life from here.
Allen, looking at his 23rd CFL season, with a professional record of more than 70,000 passing yards and twice a Grey Cup most valuable player, will be asked to show if he still belongs as the team's No. 1 QB.
McMahon, whose next completed pass in a regular CFL game will be his first, has 29 games in five NFL seasons as a backup and is being asked to show if he belongs at all.
They are approaching the game from opposite mindsets. Allen says he has everything to prove. McMahon says he has nothing to prove -- to anyone. Looking at their respective careers, some people might believe they've got this all backwards.
"I play the game to have fun. I don't have to prove anything. I've had a great career so far," McMahon said this week. "With all quarterbacks, it's about finding the right fit, the right system, getting the right players around you. That's what it's all about."
He never found it with the Detroit Lions, for whom he started three games in 2001 as a rookie, and only one game three years later. He never found it in Philadelphia where, despite starting nine games in place of Donovan McNabb in '05 -- passing for a career-best 299 yards against the New York Giants in one outing -- he lasted just one season. He never found it last season with the Vikings.
Has he found it in Toronto?
"I don't know. We'll have to go on the field and see," McMahon said. "You can only do so much in practice. We've only had one pre-season game and I learned a lot. And, I expect I'll learn a lot more in this game."
Allen has been the Argos' undisputed leader through four seasons, but last year he was plagued by injuries and Michael Bishop twice came off the bench with heroic efforts in the playoffs. But Allen is a remarkable athlete -- a combination of Brett Favre's determination, Warren Moon's elegance and Michael Vick's footwork. He is also 44.
"I've felt I had to prove something every year that I've been in this league. So it doesn't change for me 23 years later," Allen said. "As long as I've been here, especially getting into the upper echelon of age. I don't think I always said I was the No. 1 guy. I've always felt I had to prove that I was still worthy of playing this game and of being the starter. So in my own mind nothing has changed."
He knows people are wondering if he might be on the downslope that all athletes face eventually. It is something, Allen said, that pro athletes themselves cannot afford to contemplate.
"I don't think we ever prepare for someone to take our job," Allen said. "We're in a competitive atmosphere. You have to have the mindset that you're the best."
Allen, who didn't play in the first preseason game, is expected to play the first half tonight. McMahon will get a chance in the second half to see how much he has adjusted to a game he has seen mostly only on film and in practice.
"In the NFL," McMahon said, "you get the adrenalin pumping and, the next thing you know, you've overthrown the receiver. Here you can let that adrenalin pump. With the wider field, you can let the ball go because here the ball travels a lot further and you've got to give the receivers time to get to it. I'm starting to learn not to hold back."
Right now, it looks like this: Allen is guaranteed a place as the starter or as tutor to Bishop. With Eric Crouch looking as if he'll go on injured reserve. That would leave McMahon as the potential third-stringer, facing a steep learning curve and a clipboard. Question is, would he stick around?
"I'm not sure," he said. "I feel I can be productive on the field. It's a case of getting repetitions. Sitting on the sidelines, you only learn so much. You have to play."
And, to play, he has to prove he is worthy. Allen learned that years ago. It's the difference between going to the Hall of Fame and going, well ... nowhere.