Zimmerman, who won his Gold Glove in 2009, has provided an answer: He feels more comfortable throwing now than he ever did before. After a shaky start to his mechanical change, Zimmerman has made only two throwing errors since August began, a span of 37 games. The first came Aug. 16 against the Reds, when he charged the ball and made a running throw. The second came Sunday, when Zimmerman backed up to field a high hop and fired the ball across the diamond, off of Chris Marrero’s glove.

With constant pregame practice and tweaking, Zimmerman has alleviated concerns about his throwing and, if anything, improved on the defense that already made him one of the league’s best defensive players.

“I’m very happy with how far I’ve come this year,” Zimmerman said. “Now I can kind of carry this momentum and use it in the offseason to be even better next year. From where I was to where I am now, I’m very happy with the way it’s gone.”

When Zimmerman returned from surgery June 14, he began working with Nationals infielder coordinator Jeff Garber to change his throwing form. He used more flexion in his elbow and threw more over-the-top rather than sidearm, and he used his legs more and his core less.

“It’s more consistent and it’s more efficient,” Zimmerman said. “It’s going to help the longevity – I plan on being a third baseman for a long time, and when I’m done, being one of the best third basemen who played for a long time. A lot of people have a couple good years. There’s nothing bad about that – it’s hard to have one good year. If you do little things to change your style through your career, and it’s going to help you be a better player for a longer time, that’s the goal. That definitely is one of the reasons I did it.”

Routine plays to Zimmerman, for a span this season, gave you reason to hold your breath. He made seven errors in his first 40 games back from injury, and many of the throws that did reach first base did so on a hop. His form looked awkward at best, awful at worst. At one point, when he had made four throwing errors in a span of 10 games, his throwing was a significant issue.

Zimmerman recognized his injury as an opportunity to make the change, even if it meant growing pains in the middle of the season. The sacrifice, he thought, would be worth it. Zimmerman plays constantly on an even keel, and he never exactly worried about making the switch. But trying to make a drastic change on the fly challenged him physically and mentally.

“The first month or so was tough,” Zimmerman said. “Any time, learning anything new is tough. To do it in front of 30,000 people every night is a little bit more awkward. You know people are watching. That’s a thing I had to do, and I’m proud of the way I worked and get better at it.

“It’s not that I felt uncomfortable. But my level of comfort might not have been as high. But now, I think I’m more comfortable now that I was before.”