Sunday’s game against the New York Mets served as a fine summary of Craig Stammen’s season.

The 26-year-old was one of the Nationals’ best pitchers in spring training and he has shown flashes of that talent in 2010. But opposing batters have too often bruised Stammen, too, and he hasn’t always kept his composure during those trying times.

That was a big reason why he was the odd-man out of the starting rotation when rookie Stephen Strasburg was ready for his promotion to the big leagues last month. Stammen fought his way back from Triple-A Syracuse after just three starts there in June. And after last Tuesday’s sparkling two-run, five-hit effort against the Atlanta Braves he seemed back on track.

At least it appeared that way until he faced the Mets in front of a July 4th holiday crowd of 29,234 at Nationals Park. Jason Bay tripled home two runs in the first inning and drove in four total as New York battered Stammen en route to a 9-5 victory.

Stammen gave up seven runs on eight hits – four for extra bases - and three walks in just 3 1/3 innings. So what happened to the guy who pitched into the eighth inning against the Braves in his first start back from Syracuse and gave up just five hits and two walks? Or the right-hander who allowed one run in his final 13 2/3 minor-league innings?

“My pitches didn’t look a whole lot different, did they?” Stammen asked the assembled media after the game. “But that’s been my thing the whole season.”

Stammen met with pitching coach Steve McCatty for several minutes afterwards. But they weren’t talking much about physical issues. With Stammen this season the problems come from the mental part of the game – staying with a gameplan, shaking off bad pitches and throwing the ball with more conviction. Only Livan Hernandez has more quality starts for the Nats in 2010 than Stammen’s six. Yet he is 2-3 with a 5.73 ERA in 14 games.   

Mets first baseman Ike Davis hit a two-run homer off Stammen in the third inning. Angel Pagan had an RBI single and double and Jeff Francoeur doubled home a run off Nats reliever Miguel Batista. By the top of the fourth inning it was 8-0 New York and the game was all but over.

“It’s very frustrating because once you figure you’re in the right mindset and that you’re throwing the right way you feel like you can duplicate that,” Stammen said. “And then to go out there like I did today - I didn’t really duplicate that.”

Ryan Zimmerman did hit a three-run home run in the sixth inning as Washington tried to rally. But the Nats left the bases loaded in the sixth and runners at second and third in the seventh. Zimmerman, who finished the day 3-for-5, added a run-scoring single in the seventh and Wil Nieves did the same in the eighth. But it was too late and Washington’s final push in the ninth fell short, too.

Singles by Cristian Guzman and Zimmerman set the stage with nobody out. But Mets’ closer Francisco Rodriguez induced a fielder’s choice grounder from slugger Adam Dunn and then struck out Josh Willingham. Rodriguez earned his 20th save of the season when pinch hitter Roger Bernadina hit a hard ground ball that Davis dove for and tossed to the pitcher covering for the final out.

New York starter Hisanori Takahashi pitched five innings, plus four batters in the bottom of the sixth. He allowed three runs – all on Zimmerman’s homer – with five hits and two walks. Takahashi also tied a career high with seven strikeouts. The last-place Nats (36-47) still split the four-game weekend series with the Mets (46-36), who remained in second place in the National League East. Takahashi is now 7-3 with a 4.32 ERA.