What an improved changeup could mean for Zimmermann, plus plans for Rendon

VIERA, Fla. - We've been here before, with Jordan Zimmermann feeling like he's turned a corner with his changeup, so to speak. Zimmermann has been working on his changeup for three straight years, hoping to get it to the point that he has enough confidence in the pitch to use it in games. Last year, Zimmermann thought he was at that point. He worked on the changeup for much of the early part of spring, felt it was improving, and then barely touched it during the regular season. That led Nationals rehabilitation coach Mark Grater to crack a joke to Zimmermann recently. Grater told Zimmermann that he has a February changeup, meaning once the calendar turns, the changeup disappears from Zimmermann's arsenal. "Today is March 1, so I guess it hasn't gone away," Zimmermann joked after his start last night. "Hopefully it sticks with me for a little while." Zimmermann was already on his way to being one of the better young pitchers in baseball even without the changeup being much of a factor. He threw the pitch just 2.2 percent of the time last season, relying on his mid-90s fastball (thrown 63 percent of the time), his hard 86-87 mph slider (used 24 percent of the time) and a curve that registers in the high-70s (which he worked in 12 percent of the time). Even using predominately just those three pitches, Zimmermann was trending upwards, and he finished last season 12-8 with a 2.94 ERA and 153 strikeouts in 195 2/3 innings. If the changeup keeps improving and is here to stay, however, and Zimmermann can continue to have as much confidence in it in, say, July, as he did last night, he could become even more dangerous. The changeup could keep hitters honest, and make his fastball and slider seem like they have even more juice than they actually do. "It just adds to his arsenal," manager Davey Johnson said of Zimmermann's change. "That's a great pitch, because basically everything (else he throws is) hard. All his pitches are good, but when you can get them off the hard stuff with something like that, hitters were taking funny swings on it. And he stayed off it up until now, but now if you talk to him, I think he'll say, 'Yeah I like the pitch.' "His arm strength and his command, he's always way up there off the charts on that stuff. But adding this pitch just makes him that much tougher. And I think he realizes he's thrown some good ones." Zimmermann's still got a ways to go with the changeup. He needs to keep getting a feel for it in his spring starts, making sure the arm action is the way he wants it and the pitch's velocity stays in the 83-85 mph range, just enough of a difference from the fastball and slider to be effective. Then he'll need to go about learning when to best throw the pitch, which is yet another hurdle. "That's going to be a learning process," Johnson said, "but it's such a good pitch that he's had good command of it, good delivery. It's something he'll get better with as he goes and learn how to use it." Meanwhile, Anthony Rendon made his first spring appearance at shortstop during last night's game. The Nationals' top prospect played three games at short last spring in addition to three games at third base (his natural position), but then ended up playing strictly at third during the minor league season. Johnson wants to get Rendon time at both of those spots while he's in big league camp, giving him experience there should something happen to Ryan Zimmerman or Ian Desmond. "I like him on the left side of the infield," Johnson said. "Last spring, I played him at short. There's kind of a logjam at third. A bunch of guys can play third, but he's such a talented individual, I'll put him in at short and third. He's comfortable there." As for Rendon possibly seeing time at second base, as well, Johnson says that's possible, but he wants to work with the 22-year-old infielder a bit more on his fundamentals over at second base before having him play the position during a game. Also, as much as Johnson wants Rendon to have experience at multiple infield spots, he doesn't want to spread him too thin and overload Rendon's head with too much information. "He has a real good aptitude," Johnson said. "He has that good footwork (at second), but it's something I want him to be real comfortable with before he goes over there. And really, once you get the footwork down, you hate to put him (at second base) and then move him back to the other side. I want him basically over (on the left side) until they're sure of where they need him down the line." The Nationals have a 1 p.m. game against the Cardinals at Jupiter this afternoon. It'll be Gio Gonzalez against Adam Wainwright in a rematch of the starters from Game 5 of the National League Division Series. The stakes are just a little bit lower this time.