Last season, the 29-year-old North Vancouver, B.C., native had to be replaced because of an injury. On Monday, he will do the replacing as he fills in for injured teammate Kirby Fabien against the Winnipeg Blue Bombers.
Valli, who battled a knee injury last season and lost his starting job to rookie Fabien at the outset of the current campaign, personifies the prevalent themes of redemption and opportunity as the Lions (3-2) and Bombers (1-4) look to make amends after losing their previous games.
He gets the call after Fabien underwent reconstructive knee surgery Friday in wake of being sidelined early in a loss Tuesday in Toronto.
"It's what they keep me around for," said Valli, who is in the eighth season of a career spent entirely with the Lions. "You keep a veteran guy because you know when it hits the fan, you can count on him. I'm glad that I'm able to contribute in that way."
Accordingly, Valli, who took Fabien's place for most of the game in Toronto, does not see his role reversal as a big deal.
"To be honest, I've done a lot of interviews this week, and people are asking questions like I've never started a game before," he said after a walk-through Sunday.
"I started in the (2011) Grey Cup against these guys. I've played the Bombers, probably, 16 times, in my career. So it's nice to be back in the lineup, but it's all in a day's work."
Valli can relate to Fabien's plight, because he had two surgical procedures performed on his wonky knee after he was sidelined on the first day of training camp in 2012.
The first, performed before the season, repaired a torn anterior cruciate ligament while removing two-thirds of it. The second, completed after the season, replaced the missing portion of ligament with tissue from Valli's hamstring.
"Last season was the first season I've really faced any sort of injury adversity in my whole career, and it was tough," said Valli, a product of Simon Fraser University. "It kind of opens your eyes to things, but I think I'm a bigger man for it this year.
"You realize you play the hand you're dealt. You can sit and feel sorry for yourself and pout, or you can just do what you're asked to do. When you do that, generally, things will go your way."
The Lions are hoping things can go their way more often in the red zone. B.C. got within 10 yards of Toronto's end zone on four occasions last Tuesday, but had to settle for a field goal every time while suffering a 38-12 setback.
B.C. went without a touchdown for the first time in 131 games, dating to 2005, and quarterback Travis Lulay ended a 36-game touchdown-passing streak.
The offensive line will play a major role in pushing the Lions across the goal-line. But Lulay thinks Valli will be up for the occasion.
"It's a luxury to have a guy like Dean, who's played a tonne of football games, be a guy that's coming off the bench," said Lulay. "Dean's a guy who was injured a bit last season, (and is) just getting over that coming into this season. So he's excited to be getting back into the lineup. It's good to see that fire.
"He's still got it."
Fabien's injury is not the only one posing a challenge for the Lions. Slotback Nick Moore (ankle) is slated to be replaced by rookie Korey Williams, also a kick returner, who has been in and out of the lineup this season. Meanwhile, B.C. wide receiver Emmanuel Arceneaux draws back in after sitting out the Toronto game with an ankle injury.
Williams and Arceneaux add to the redemption-and-opportunity theme as the Lions return to B.C. Place Stadium still reeling from their loss to the Argos.
"Certainly, there's no doubt, after you lose a football game, you're going to be a little bit more anxious," said Lions coach Mike Benevides. "You're going to be a little bit more angry. And, certainly, the attitude is the right one.
"But I know the Bombers are going to be in the same mindset. Both teams are angry and looking for a win, and it should be an outstanding ball game."
Winnipeg, which lost 37-24 to Calgary in its last outing, will attempt to halt a three-game losing skid. Bombers coach Tim Burke said a victory over the Lions will be a boost as his club tries to change its lagging fortunes.
"Certainly, we would like to win this game to give us some positive momentum going forward," said Burke. "The schedule gets a little bit more favourable to us here after the bye (next week). So if we can get some positive momentum going, I think that would help us."
Against the Lions, the Bombers will be looking for momentum from starting quarterback Justin Goltz. The 25-year-old Walled Lake, Mich., native, enters the game as the club's official starter for the first time, after he was promoted last week.
Goltz, who started in the July 26 loss to Calgary, has faced more media scrutiny this week, notably after dethroned former No. 1 signal-caller Buck Pierce criticized the move. Burke said Goltz has put more pressure on himself as a result of the extra attention, and coaches have tried to stress that nothing has really changed in the past week.
"He's gotta learn to let that (public pressure) roll off his back, just like the head coaches have to," said Burke.
But Goltz, who is in his fourth season with the Bombers after signing in October, 2010, said he does not consider his new status special.
"Really for me, it hasn't been a whole lot different, other than the media (coverage)," said Goltz. "Behind closed doors, there's been a lot of work in the past couple seasons that people haven't seen. But I've been preparing for this day for a long time."
Meanwhile, the Blue Bombers will also have some injured players return.
Wide receiver Chris Matthews returns along with nickelback Desia Dunn, and defensive back Jeremy McGee will make his 2013 debut.
"We'll be definitely a better team hitting the field than we were the last couple weeks," said Burke.