''I don't want to say it's a make-it-or-break-it year, but I know it's definitely a very important spring right now,'' Manuel said following a voluntary veterans minicamp session this week. ''Obviously, the third year is where a lot of NFL quarterbacks that are starters really show that, `Hey, this guy can be a longtime starter for this team.'''
The jury is still out on Manuel, who has been inconsistent at best since being selected 16th out of Florida State in 2013. He went 4-6 and missed six games as a rookie due to three separate knee injuries. Last year, Manuel lost the No. 1 role after a 2-2 start, and was replaced by journeyman Kyle Orton, who has since retired.
General manager Doug Whaley was blunt in assessing the status of the Bills quarterback position last week by saying: ''We don't have a proven franchise quarterback.''
Manuel's inability to lock down the starting job - a role that has remained unsettled in Buffalo since Hall of Famer Jim Kelly retired after the 1996 season - is a hot topic of concern entering the draft. That's because the Bills lack a first-round pick, giving them no realistic option of selecting a proven quarterback prospect.
The Bills traded this year's first-round pick to Cleveland a year ago to move up five spots and select receiver Sammy Watkins fourth overall. Buffalo, which would have selected 19th, instead opens the draft in the second round on Friday, when it picks 50th.
Though Whaley hasn't ruled out drafting a quarterback, the scouting grades are inconsistent for the crop behind Jameis Winston and Marcus Mariota.
Manuel would be fine if the Bills added another quarterback to the mix, which also includes former practice squad player Jeff Tuel.
''Welcome to the team,'' Manuel said, when asked what his reaction might be. ''Come in and be ready to work, and fall in line.''
At the very least, Manuel gets the opportunity to make a good first impression under a new coach in Rex Ryan, who took over in January after Doug Marrone abruptly stepped down following a 9-7 finish. Manuel acknowledged he's not sure where he would have stood if Marrone returned.
''I just think God works in mysterious ways, and I'm excited with the coaches we have now,'' Manuel said with a smile. ''I think it's a clean slate for myself.''
Both Ryan and new offensive Greg Roman are keeping an open mind.
''Whatever happened prior, good bad or indifferent, it just doesn't factor in,'' Roman said. ''So it's really simple: Here we are, fresh start, new everything, and let's see what we've got.''
Ryan liked what he saw from all three quarterbacks when the team opened its first on-field session on Tuesday.
''The thing I noticed about Cassel, the ball comes out in rhythm,'' ''Ryan said. ''It's boom! Boom!''
As for Manuel, Ryan said: ''EJ was impressive to me today. I'd still like to see it speeded up just a tad.''
That has been the knock on Manuel. At 6-4 and 237 pounds, he has the size and ability to play the position, but has at times been hesitant in the pocket.
Overall, Manuel has completed just 58.6 percent of his attempts, with 16 touchdowns and 12 interceptions.
Manuel spent the offseason working on his technique with former NFL quarterback Steve DeBerg. He also called last year's demotion a motivating experience.
''I definitely learned a lot about my manhood and about myself, about what I can handle and what I can take,'' Manuel said.
Veteran running back Fred Jackson has noticed a difference in Manuel.
''It's just about getting the mental part down. And that's where I think he's improved the most,'' Jackson said. ''He knows the challenge in front of him. And it's one that he's willing to accept. That's all we can ask of him.''
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