WASHINGTON -- Francisco Liriano knows what it feels like to pitch an entire game without allowing a hit.
Good as he was Wednesday night, the Pittsburgh Pirates left-hander wasn't about to allow his mind to start wandering in that direction too soon.
Liriano did not allow a hit until the sixth inning against a struggling and depleted Nationals lineup, and Pedro Alvarez homered off an otherwise-dominant Stephen Strasburg, leading Pittsburgh past Washington 4-2.
"Everything was working the way I wanted," said Liriano (10-4), who wound up giving up two singles across 7 2/3 innings while striking out eight batters.
Liriano threw a no-hitter for the Twins against the White Sox on May 3, 2011, but on Wednesday, he said, "I think (it) was too early in the game to think about it. It was the fifth inning. I just want to give a chance to the guys to win a ballgame."
He managed to do just that on a night that Nationals right-hander Stephen Strasburg (5-8) was terrific.
Strasburg struck out 12 and did not walk anyone in eight innings. He gave up only one run and two hits, all in the second inning. That included a leadoff shot by Pedro Alvarez, who drove a 96 mph fastball over the wall in right-center for his 26th homer.
Pirates manager Clint Hurdle said the homer gave him goose bumps.
"The wind is blowing in. When that ball is hit, I'm thinking, `OK, he's on second.' And then I see some fans stand up and I go, `Wait a minute.' ... A backspin 2-iron. I've seen a lot of home runs. I've seen a lot of hard-hit balls," Hurdle said. "But that one got my attention."
It was Strasburg's ninth career game with 10 or more strikeouts and first this season. His career high remains the 14 Ks from his major league debut on June 8, 2010, against Pittsburgh.
But the Nationals fell to 0-6 since the All-Star break -- scoring a grand total of 13 runs in that span -- and have lost 11 of their last 13 games.
"We need to win some games," Strasburg said. "It's getting to the point where our back's against the wall."
Liriano walked the first batter he faced, then retired 11 in a row before another walk. Five more outs followed, before rookie Anthony Rendon reached on what was ruled an infield single with two away in the sixth.
Third baseman Alvarez dove to his left to stop the ball, but it popped out of his glove, and he couldn't quite corral it. The next batter walked, but Liriano struck out cleanup hitter Jayson Werth looking to end the inning.
The Pirates tacked on three insurance runs in the ninth against relievers Drew Storen and Fernando Abad, thanks to Neil Walker's RBI double and Michael McKenry's two-run single. That became pivotal when Werth hit a two-run shot, his 15th homer of the year, off reliever Justin Wilson in the bottom of the ninth. Werth is seemingly the only Nationals batter capable of producing at the moment; he's hit five homers in the past four games.
"Not even close. He never tagged me," Ramos said.
He argued the call with umpire Laz Diaz, to no avail.
"Maybe," Ramos said, "he (wanted) to go home."
Nationals spokesman John Dever declined to check whether the umpiring crew would respond to reporters' request for comment.
Melancon is filling in for closer Jason Grilli, on the disabled list with a strained right forearm. ... The Pirates play 14 of their final 59 games against the St. Louis Cardinals, the team Pittsburgh trails in the NL Central standings. "It is unique. I think it kind of pushes you," Hurdle said. ... On Thursday, the Pirates will start RHP A.J. Burnett (4-7, 3.07) against Nationals LHP Gio Gonzalez (7-3, 2.89).
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