WASHINGTON -- Roy Oswalt was cruising through the Washington Nationals lineup with incredible efficiency, seemingly on pace for the shutout.
Then came a moment of indiscretion so stunning it froze the umpires. With two outs in the sixth inning and an 0-2 count on Alfonso Soriano, the Houston Astros ace interrupted his windup and started walking toward baserunner Damian Jackson on third.
That's a balk. Jackson was awarded home to tie the game, Oswalt was lifted for a pinch hitter in the eighth, and the Nationals exploited the Astros' bullpen with a four-run eighth to take a 5-1 victory Wednesday night.
"I knew I did it," Oswalt said. "I've never lost a game because of balking, but we pretty much lost the game right there. We had complete control of the game and with two strikes on Soriano, I thought I could get him fishing at something outside of the zone. We should have won that game, 1-0. I felt I had good enough stuff where I felt I could keep them off the bases."
As obvious as the balk was, Oswalt nearly got away with it. The umpires were silent until Nationals manager Frank Robinson walked onto the field and approached home plate umpire Larry Young, who called the other three umpires together before pointing Jackson home.
"It should have been called by me initially," Young said. "We saw it on replay. It was an obvious balk. I didn't call it. I had a question in my mind whether he was on the rubber or not, but I deferred to my partners. They said he was definitely on the rubber, so therefore it was a balk, but I feel in retrospect that I should have avoided that situation altogether by calling it immediately because it was so obvious."
Oswalt was otherwise masterful, allowing two hits, striking out seven and facing only two batters over the minimum over seven innings. He had retired 14 straight batters before Jackson doubled to open the sixth and advanced on a groundout to set up the balk.
"We were glad to see him go," Robinson said. "He was almost unhittable."
With Oswalt gone, Ryan Zimmerman led off the eighth with a triple off Dan Wheeler (0-3). Jackson struck out, then Brad Lidge came on and failed to retire any of the four batters he faced, allowing RBI hits to pinch-hitter Daryle Ward, Soriano and Royce Clayton and allowing another run on a wild pitch. Lidge's ERA ballooned to 6.53, and the Astros are 1-2 at the start of their 10-game road trip.
"We had a team that was really flat after thumping them on Monday night, and we put them back in the series," Houston manager Phil Garner said. "And now we have to scramble just to split with them."
The Nationals won their fourth in five games, but they had to wonder if some sort of hex was afoot when two starters left early with bizarre injuries.
Right fielder Jose Guillen could only play two innings because of an eye injury, suffered when he tried to scratch his left eye with his batting glove during batting practice. Catcher Wiki Gonzalez was gone after three innings, injured when he was hit in the head by Preston Wilson's backswing in the second. Gonzalez was diagnosed with a mild concussion and a strained neck muscle.
But Nationals rookie starter Mike O'Connor kept the Nationals competitive with six strong innings, allowing three hits and only one run -- Morgan Ensberg's second-inning homer, his 16th of the season. The win went to Gary Majewski (2-2), one of four Nationals relievers who combined to pitch three scoreless innings.
Still, the Nationals doubt they could have won without the balk.
"What surprises me about that call is that nobody said anything in the first place," Garner said. "OK, he balked, but none of them? I understand Larry's point, he can't see when he's on the rubber. But the other two guys at first and third, they've got to see it and somebody's got to say something."
Washington's Santiago Ramirez, one of two relievers brought up from Triple-A New Orleans on Monday, made his major league debut by pitching a scoreless seventh inning. ... Guillen was playing his second straight game after missing five with a strained right hamstring. He struck out in his only plate appearance before leaving with the eye injury. ... The Astros have lost eight of their last 10 on the road. ... The game was the 100th at RFK Stadium since baseball returned to Washington last year. ... Before the game, the Nationals players and front office staff held their first meetings with the new ownership group that is expected to take over in a few weeks. "It was a kind of a quick meet-and-greet," shortstop Royce Clayton said.