INDIANAPOLIS -- Curtis Painter's disappointing senior season has gotten worse.
The Purdue quarterback had what coach Joe Tiller called a slight-to-moderate right shoulder separation against Minnesota last weekend, putting his nation-leading streak of 40 consecutive starts in jeopardy heading into Saturday's game against Michigan.
"It will be more up to the player than anyone else," Tiller said of whether or not Painter will play. "He's the guy that knows how he feels. I trust Curtis and I think he's honest. I think if he can go, he'll say he can go."
Painter and the Boilermakers (2-6, 0-4 Big Ten) remain in contention for a bowl bid, but his struggles have led to plenty of postseason uncertainty.
Though Painter has been durable, he has also led the Boilermakers' offense through its worst stretch in Tiller's 12 years as coach. Purdue has scored single-digit points in three of its past four games and failed to reach the end zone twice in that span.
With the Boilermakers mired in a five-game losing streak, Painter has completed just 54 percent of his passes for 1,008 yards with three touchdowns and seven interceptions.
Last season, Painter passed for 3,846 yards and 29 touchdowns and led the Boilermakers to a school record for points in a season. He threw for a Big Ten-record 3,985 yards as a sophomore.
Painter started this season as a Heisman hopeful who was projected by experts to be an early-round draft pick next April. Instead of progressing, he has played his worst football statistically since his freshman year.
Painter reached several career milestones this season amid the mediocrity. He has more than 10,000 career yards passing and needs 56 more to move past Brett Basanez of Northwestern into second place in league history behind former Purdue quarterback Drew Brees.
Even with the big career numbers, there was uncertainty if Tiller would start him against Minnesota.
Painter got the start but was knocked out on Purdue's first offensive series. Justin Siller stepped in and made some plays, but couldn't consistently move the team. He completed 10-of-17 passes for 73 yards and ran for 17 yards.
Siller and Painter are listed as co-No. 1 quarterbacks. Tiller said the Boilermakers would be ready if Siller had to start.
"We assume we're going to have him [Painter], but we need to prepare as though we're not going to have him."
Tiller said Siller will play some, regardless of Painter's condition.
"The fact that we're going to practice Justin more this week would also suggest that you're going to see Justin, no matter what the status of Curtis is."
Siller was a running back until the Northwestern game on Oct. 18, when No. 2 quarterback Joey Elliott was knocked out for the season with a separated shoulder. That forced Tiller to move Siller back to quarterback, his original position.
Siller is more athletic than Painter and much more likely to run on a broken play. He lined up at quarterback several times before the Minnesota game but never threw a pass.
The Boilermakers are adjusting their playbook to account for Siller's set of skills.
"I think this week we'll be closer to having a similar package for the two of them because he'll [Siller] have another week back into the offense," Tiller said.
Tiller said Siller played well at quarterback in the spring, but didn't improve enough in the fall to move past Elliott. His athletic ability made the staff consider a different way to get him on the field, so he was moved to running back.
Now, with Elliott out, Siller might get a chance to prove he is the quarterback of the future for the Boilermakers. If Painter isn't careful, Siller could become the quarterback of the present.
"There is a silver lining to every cloud," Tiller said. "As Justin plays more and more and more, you'll get more answers."