Wilson went 3-for-3 with two RBI and two runs scored in a 12-5 win over the Houston Astros. The 25-year-old shortstop raised his batting average from .222 to .417.
"I've been feeling real good at the plate all spring," he said. "So it's nothing new, just getting more at-bats. You just keep working every day to get that good feel and that consistent feel and today it was there."
Wilson batted .307 with 10 homers and 45 RBI in 89 games for Triple-A Colorado Springs last season. He has played in just 11 major league games, all with the Florida Marlins in 2005.
"I think he's loosening up a little bit," Nationals manager Manny Acta said. "I think the first couple of games he looked a little nervous out there trying to impress too much. But he's been a quality Triple-A shortstop . . . so I hope this is the Josh Wilson we envisioned."
Starter Jason Simontacchi allowed three runs and four hits in four innings with four strikeouts, no walks and two hit batters.
Houston's Jason Jennings gave up four runs and five hits in three innings, struck out three and walked one. Jason Bergmann pitched three scoreless innings of relief for the Nationals, keeping his ERA at 0.00 in five innings.
Houston's Jason Lane was 3-for-4 with a home run, double and two RBI. Hunter Pence hit a two-run homer.
Houston C Hector Gimenez had surgery to repair his labrum. He is expected to begin throwing in about three months.