When he's stationed at the hot corner, Ryan Zimmerman has the tendency to do the remarkable. I can't even count the number of head shakes Zimmerman has gotten from those of us in the press box this season after another ridiculous stab of a sharp grounder, dive to snag a hot shot or web gem on a tapper down the line. Every now and then, however, Zimmerman gloves a ball, and with plenty of time to make a throw to first, he sprays the throw off-line. Often times, the hurried throws - ones where Zimmerman throws sidearm or three-quarters - are right on the money, and first baseman Adam LaRoche barely needs to move. It's the ones where Zimmerman has time to think where he makes the vast majority of his throwing errors. Those are the types of plays which Davey Johnson admits concern him a little bit, although the Nationals manager's level of worry is minimal. "Yeah, I mean, that's the shoulder he's had the problem with, with the shots," Johnson said. "So I'm sure there's probably a little impingement in there or something. When you don't get (the throwing arm) up there and cut it loose, you're going to have some problems as well, because it's hurting you, causing a little discomfort. So it's probably part of both. But he's awfully good the way he is. I'm not worried about it." Two nights ago, the Cardinals scored their lone run of the game largely because Zimmerman airmailed a throw over LaRoche's head after gloving a routine Jon Jay ground ball.

On plays like that, where he has plenty of time, Zimmerman cocks his right arm back in a robotic-looking motion and throws over the top. It's a strange looking motion, but it's one the Nats have asked Zimmerman to use when he has time to set and throw to first. But it's clearly not entirely comfortable for Zimmerman yet, which begs the question - Are his throwing issues more mental or mechanical? "I think both probably," Johnson said. "I like (simply) fielding and throwing. I like when he (whips it across his body). And when he throws overhand ... Brooks Robinson, when it hit him ... it was coming. There was not any setting. (Luis) Aparacio, on the other hand, would just set it right there (behind his shoulder) and wait 'til the guy got one step away and go, 'Foomph!' "I think it's a little bit of both. I like it when he cuts it loose more than when he just (sets and throws overhand.)" The throwing issues with Zimmerman go back a few years. A couple seasons ago, the Nationals told him to throw sidearm on every play, knowing that he was more accurate that way. But when Zimmerman spent a large part of last season on the DL with a torn abdominal, the Nationals tried to get him to change his motion and throw more over the top. Their thinking was that Zimmerman's sidearm throwing motion either contributed to his injury or could exacerbate it after his return. That's why the overhand tosses have returned, and with them, so has some of the wildness. "I wasn't here during that process," Johnson said. "I had a guy that had a little problem throwing to first, a switch-hitter I had in New York, Howard Johnson. He occasionally would start cunny-thumbing it over there to first. And I said, 'Look, I want you to just throw it over there, as hard as you care. I don't care if it lands 15 rows up, that's fine. But don't be aiming nothing over there, just cut it loose.' "I don't worry about things like that, just as long as they get it and throw it." For now, however, Zimmerman will keep throwing over the top when he has time. And those head shakes of amazement after a strong defensive play might continue to be joined by a few head shakes of confusion after the shaky throws.