The optimism that permeates most big league players when they start spring training wasn't quite there for Justin Morneau on Friday. There certainly wasn't pessimism, either, for the former AL MVP who is coming off another injury-plagued season.

At this point in the Minnesota Twins first baseman's career, there is only realism.

He feels good, but knows he can't guarantee that his concussion problems are behind him. He is confident that he can get back to his All-Star form, but nervous as well because he's not sure how many more rehabilitation programs he has left in him.

"I don't think there will be a career if it's something I'm dealing with (for the long term)," Morneau said before the Twins held their first full-squad workout of spring training. "That's the reality of the whole thing. I'm obviously not going to continue to mess around with this if it continues to be a problem.

"There comes a point where you can only torture yourself for so long. It's something I love to do but you keep preparing and you keep being left out," he added. "That's something that nobody wants to go through."

He participated fully in the workout Friday, taking grounders at first base, popping a couple of home runs during batting practice and standing in against a pitcher to work on his timing.

"If people are getting excited and worried about him being honest then that's too bad," manager Ron Gardenhire said. "He should have concerns. Everybody should when you're talking about things like that because it's the unknown. But I think he's fine, from everything we've seen he's doing good. He had a good day today, and we just go from there."

Morneau also missed games over the last two years with neck, back, left knee, right foot and left wrist injuries, but said he wasn't worried about those holding him back. He's still gaining some strength in his wrist after surgery and has some numbness in the index finger on his left hand from a neck procedure. But he expects both conditions to improve this spring.

He's dropped some weight with a change in his diet, reducing the stress on his ankles and knees. Morneau said he feels strong enough to go through all the workouts without limitations.

It's the concussions that concern him.

He was hit in the head while sliding into second base at Toronto on July 7, 2010, and missed almost all of the rest of that season while recovering. Then the symptoms resurfaced last year. He hit .227 with four homers and 30 RBIs in 69 games, and needed four operations — on his neck, wrist, foot and knee.

"The only thing right now that I'm worrying about coming back or bothering me as we go along is the concussion stuff," he said. "That's something that's just so unknown. There's people that have the post-concussion and deal with it the rest of their lives. It's one of those things that I don't know. I can't predict the future."

Coming off a 99-loss season, the Twins missed their franchise cornerstone, clubhouse leader and feared cleanup hitter. He was hitting .345 with 18 homers and 56 RBIs when he went down in Toronto, and he hasn't been the same since.

"It is definitely good to see him here walking around," center fielder Denard Span said. "He's definitely a big key to our success and we're definitely going to need him. If we get him back to the old Morneau, I think we'll be able to surprise some teams."

The Twins medical staff will be monitoring Morneau closely throughout the spring to see how he responds to the workload and he has yet to be cleared to play in a game. But that is considered only a formality.

"There are no restrictions," general manager Terry Ryan said. "I'm sure there's doubt. Everybody that comes in here the first couple days is going to have doubt on where they're at. But that's about the extent of it."

Morneau did say that he feels much better entering spring this season than he did last year after being able to work out for most of the winter. He's received support from his wife and advice from athletes who've had concussions, including former Twins third baseman Corey Koskie and pro hockey player Willie Mitchell.

Now he's at peace with whatever happens next.

"This year, I know whatever happens I've done everything I possibly can to be ready and to just put myself in the positions to succeed and to have a good year and to do everything that I can," Morneau said.

"I feel like I was able to do enough this winter to be prepared. If something goes wrong or if something isn't right it is not because I'm not prepared or didn't put the work in. The excitement is there."


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