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.
Wilson was replaced by Mark Melancon, who got the last three outs to earn his third save, ending with a double play on which second baseman Walker whiffed on his attempted tag of runner Wilson Ramos.
"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.
Notes: 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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