Bobby Brosnahan is characterized by his manager as a fierce competitor on the diamond. Off of it, he's the clown of the Michigan baseball team.

He tells jokes -- many of which aren't fit for print. He likes to sing, too, with the Backstreet Boys a personal favorite. That's probably not fit for the public, either.

The Pioneer High School product has helped to keep the Wolverines smiling through a season in which there haven't been many reasons to.

Michigan is a disappointing 20-31 (6-14 Big Ten) heading into Sunday's game against Purdue, and has lost 15 of its past 20 games. With the regular season set to expire next weekend, manager Rich Maloney is guaranteed to suffer his second consecutive losing season.

He now is 37-68 the past two years, after winning at least 30 games in each of his first 15 seasons at Ball State (1996-2002) and Michigan.

But Maloney and the Wolverines didn't stand much chance this year after they lost six key players for extended periods due to injury.

"I don’t think there’s any question about it," Maloney said. "Think about it, six guys? What are the chances of that? Just think, if coach (John) Beilein lost (Tim) Hardaway (Jr.) and (Trey) Burke, how good would the basketball team have been? That's what this was like, with the caliber of guys we lost.

"Do I think it would have been different without the injuries? Absolutely. But it is what it is. You just keep battling, move forward."

The Wolverines' injury list includes some of the program's best players:

• Sophomore outfielder Michael O'Neill -- Michigan's best player, No. 3 hitter and a member of the Big Ten's preseason watch list -- missed 15 games from April 4 to May 4 with a hand injury. The Wolverines were only three games under .500 when O'Neill went down, but lost 11 of their 15 games without him.
• Outfielder Will Drake suffered a leg injury running out a ground ball April 11, when he was hitting above .300 as the Wolverines' No 2 hitter. He has only one hit in nine at-bats since.
• Shortstop Derek Dennis turned down a $700,000 bonus to sign with the Tampa Bay Rays out of Grand Rapids Forest Hills Central High School. Now a junior -- the first year he could re-enter the draft -- Dennis has started only six games because of an arm injury he sustained in the first week of the season.
• Starting pitcher Travis Smith was expected back after an arm injury ended his 2011 campaign during the second weekend of the season, but has logged only one inning this year.
• Starting pitcher Kolby Wood, coming back from a shoulder injury in 2011, has logged only 2 2/3 innings spanning five games. His ERA is 16.88.
• And then there's Brosnahan, the left-handed Ann Arbor product who can't seem to stay healthy. This year is no different.

The junior pitcher was expected to be the Wolverines' No. 2 starter this year, and he delivered in his first five starts, carrying a 2.10 ERA. But he knew something wasn't quite right with his arm, which easily fatigued.

Then the wheels came off.

Brosnahan's velocity was OK -- only a few miles per hour off his usual gas of about 90 miles per hour -- but his arm strength worsened. His curve ball flattened out, and he didn't have a feel for his changeup.

The result: He got lit up by Minnesota on March 31, allowing eight runs in 1 1/3 innings.

"That was by far the worst start I ever had in my career," Brosnahan said. "It was embarrassing. I was trying to pitch through (the injury), because I knew how much the team needed me, but it got to the point where I knew I wasn't helping anyone and I just needed to shut it down."

The diagnosis was rotator cuff impingement. The only cure was rest.

So, Michigan lost its third starting pitcher of the year and the staff fell to ninth in the Big Ten in ERA. The losses piled up.

It was a frustrating experience for Brosnahan, who was poised for a big year after spending the offseason in the prestigious Cape Cod Baseball League. Instead, he was sidelined again -- after missing his senior season of high school and true freshman season at Michigan because of Tommy John surgery -- and his team sank without him.

"To get hurt, it just takes the wind out of your sails," Brosnahan said. "You just work as hard as you can to get back ... but it's disappointing, sitting on the bench watching your team lose, knowing there's nothing you can do."

He's finally getting healthy, after pitching 2 2/3 innings of scoreless relief against Iowa on May 5. He got his first start Wednesday, when he held 29th-ranked Coastal Carolina scoreless in three innings.

Brosnahan's return to health comes too late to help the Wolverines turn things around this year -- they have only four games left, including a season-ending three-game series against visiting Nebraska that begins Thursday -- but it provides momentum heading into the offseason.

He'll return to the Cape Cod league this summer, then hopes to rejoin the rotation next year as the Wolverines try to get untracked after two miserable seasons.

"You got to keep growing as a team, and that’s what they’ve done, even though they've been handcuffed a little bit," Maloney said. "But the great thing is there are some young guys who are getting experience.

"Hopefully, that pays dividends for us next season and we can get this thing going."

Kyle Meinke covers Michigan football for AnnArbor.com. He can be reached at 734-623-2588, by email at kylemeinke@annarbor.com and followed on Twitter @kmeinke.