What's wrong with the Nationals' Stephen Strasburg? Problem is, no one knows...

As Stephen Strasburg described it on Friday night, the issue with the trapezius muscle in the left side of his neck, which resulted in his early exit in Cincinnati, was something new. After he'd struggled with an alignment problem in his back recently, it was another issue cropping up in a series of problems which have limited his ability to do his job.

Strasburg, as he told it, went through his normal pregame routine, warmed up in the bullpen and felt fine in the first, but between innings his neck tightened up on him.

"It wasn't a pitch, really, or anything," the 26-year-old right-hander told reporters. "I never felt it on a pitch, it was just like I sat down, I don't know what it was. I just felt it start tightening up and it's pretty tight right now too."

"It felt good," until he sat down between innings, he explained. "And like I said, it was just after the first inning, I kind of just sat down and for some reason it locked up on me."

"When he got out there for the second inning," Nats' skipper Matt Williams said when asked when he first noticed a problem. "Came out of the bullpen good, went through the first inning good. Joey [Votto] hit a 97 mph fastball down and in for a homer, pretty good pitch, but then the second inning he went out there [and] it started to tighten up on him."

A day later, when Williams spoke to reporters before the second game of three with the Reds on Saturday, he didn't have much of an update, though he did go into more detail about the problems the '09 no.1 overall pick is dealing with as he tries to figure out what's behind the consistent physical struggles Strasburg has experienced through the first two months.

"We've got to get to the bottom of what's going on," Williams said.

"So he's traveling back to D.C. He'll see [Dr.] Wiemi [Douoghui] on Monday. It's perplexing because it's not anything that you can point to. So Stras will go on the DL, and get this thing worked out and hopefully be back in 15 days."

The confusion, Williams said, is tied to the fact that Strasburg has had a number of different problem areas.

"Last night's in a different spot," he said. "It's in his left neck, trap, but something is causing him discomfort in his upper back and the fact that it switched sides, it wouldn't point to anything structural, so we have to figure it out though, because it's not allowing him to be free to pitch and do the things that he wants to do."

It's not just affecting Strasburg, of course. Two or three-plus inning starts put undue pressure on the bullpen.

"Certainly when he gets out there like last night and has to come out after the first it puts our bullpen in a spot," Williams said.

"But most of all it's frustrating for him because he's not able to do what he wants to do, so we figured it would be prudent for us to shut him down and give him 15 days to work it out and he'll see all the great doctors and all the great trainers and therapists and hopefully get over the hump so he doesn't have to have this issue again this year."

After he experienced problems under his shoulder blade/with his back/or however it was finally described, Strasburg said the issues were tied to him compensating for the ankle injury he suffered in Spring Training.

Williams said there is the possibility that it's all connected.

"You don't know, it all starts from the ground, right?" he asked rhetorically.

"So if he's got a little different feel about his ankle or he's landing in a different spot or he's compensated for it somehow going through Spring Training and the season then it's going to kind of come up the chain.

'The issue is -- for us and for Stras -- is he's never had an issue with his arm.

"It hasn't been his elbow hurting or his shoulder hurting or anything like that, so it's something to do with his back and his alignment and it could be from his ankle, it could be from the adjustment that he's made from where he's landing and having to throw across his body more, we've looked at all of that, I mean, we've exhausted everything."

Strasburg exits start early with "left trap tightness"

Photo © Andy Lyons/Getty Images

Whatever it is, Strasburg is frustrated because he can't do what he's capable of doing and can't help the team when he continues to struggle.

Through ten starts, Strasburg is (3-5) with a 6.55 ERA, a 3.95 FIP, 14 walks (2.78 BB/9) and 45 Ks (8.93 K/9) in 45 ⅓ IP, over which opposing hitters have a .389 BABIP and a .325/.377/.397 line against him.

"He's frustrated," Williams said.

"He's completely frustrated. He's not going out there and giving us a chance to win like he normally does, because he's had to come out of game so quickly, so it's important for us to get him over that. He's bummed out because he's not doing what he wants to do."

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