Gio Gonzalez against the Brewers. (AP Photo/Jeffrey Phelps)

In his second start back from a left shoulder injury, Gio Gonzalez’s velocity was noticeably down. Against the Brewers on Monday, Gonzalez’s four-seam fastball averaged 90.7 mph and he still fired six scoreless innings. It was his lowest single-game fastball velocity since a July 2010 start. In his first start back from shoulder inflammation that made him miss 27 games, however, Gonzalez averaged 92 mph, closer to his season average.

The Nationals and Gonzalez, however, are both unconcerned with the change in velocity and attribute it to normal build-up after missing a month. And when Gonzalez takes the mound again in the first game of Saturday’s doubleheader against the Cubs, he expects it to improve.

“Getting back from shoulder injury, I’m not going to throw 95 right off the bat,” Gonzalez said. “It’s definitely working your way back. Nothing to be concerned about. Just keep building from there.”

“Anytime you have any kind of injury, it takes time,” added Manager Matt Williams. Both Williams and Gonzalez noticed the drop-off during Monday’s game.

Gonzalez said pitching coach Steve McCatty assured him that he has ranged between 91 and 93 mph in starts during his career. “It wasn’t a big shock to me,” Gonzalez said.

Velocity understandably drops with age. In recent seasons, Gonzalez hasn’t had much change in velocity. In 2011, his fastball averaged 92.5 mph. In his first season, he averaged 93.1 mph and then 92.6 mph last season. In his final start before landing on the disabled list on May 18, Gonzalez averaged 92.7 mph. His season average is 92.4 mph.

Gonzalez said he expects his velocity to pick back up. But against the Brewers, Gonzalez got a chance to learn how to pitch with a slower fastball, and it worked. He allowed only three hits and struck out five against one of the NL’s best lineups. He focused more on hitting his spots instead of rearing back.

“I think it was something new for me: pitching with a low velocity,” he said. “Learn how to hit your spots. An aggressive hitting team, throw them something and — I wasn’t trying to — but that’s what came out. You learn from it. I think it was nothing to be concerned about. Just go from there.”

“It’s not velocity, it’s location,” McCatty added. “So I’m not worried about Gio’s velocity and I’m not looking at that. I have to see what our averages are. I’m not concerned about it.”

Gonzalez also used his secondary pitches more against the Brewers and it was effective. He threw 27 change-ups, about 24 percent, of his 114 pitches, the highest rate of the season. He also mixed in more curveballs than in previous starts.

“It shows him he can be effective at 90 to 91,” Williams said. “It shows him he can be effective if he uses his other pitches. He’ll be better next time.”