AP Sports Writer
PITTSBURGH (AP) -- Edinson Volquez allowed one run in six sharp innings and the Pittsburgh Pirates edged the Washington Nationals 3-1 Thursday night.
Volquez (2-4) ended a three-game losing streak by limiting the Nationals to three hits, walking two and striking out four. Mark Melancon worked the ninth for his eighth save. Andrew McCutchen drove in two runs for the Pirates and made a sliding grab with two on in the ninth to end the game. Josh Harrison added two hits for Pittsburgh.
Ian Desmond hit his eighth homer of the season for the Nationals but Washington left 10 runners on base. Rookie Blake Treinen (0-2) struggled with his command in his second career start, giving up two runs on four hits in 5 2-3 innings, striking out four and walking five. The Nationals have lost three of four.
Volquez had been a pleasant surprise during the season's first month but scuffled through his previous four starts, going 0-3 with a 10.19 ERA as part of a slide that left Pittsburgh well off the pace in the NL Central a year after making the franchise's first postseason appearance in more than two decades.
Pirates manager Clint Hurdle wondered if Volquez -- who led the National League in walks per nine innings last season -- was suddenly throwing too many strikes.
The former All-Star did a better job mixing location and speed against the Nationals. His only real miscue came on a 2-0 fastball in the fourth that Desmond sent into the seats in center field that briefly tied the game at 1.
Treinen, who faced Cy Young winner Clayton Kershaw in his previous major league start, wasn't quite as crisp. He retired the first eight batters he faced thanks in part to a sinker that topped out at 97 mph before getting loose in the third. He loaded the bases with two outs on a pair of walks and a single by Harrison before hitting McCutchen with an 80 mph changeup to force in a run.
Trouble surfaced again in the fifth thanks in part to Harrison, who has provided a spark in right field even as the Pirates mark time until the likely arrival of highly touted prospect Gregory Polanco next month.
Harrison walked to lead off the inning and moved to second on a fly to center before streaking home on a sharp single up the middle by McCutchen. Harrison is 13 for 37 (.351) since being moved into the leadoff spot earlier this month.
Washington loaded the bases in the eighth off Tony Watson, but the left-hander retired Scott Hairston on a fly to shallow left field to get out of it and Melancon survived despite putting two runners on.
NOTES: The Pirates claimed right-handed reliever Josh Wall off waivers from the Los Angeles Angels on Thursday and assigned him to Triple-A Indianapolis. Wall is 1-1 with a 15.15 ERA in 15 career major league games. To make room for Wall on the 40-man roster, the Pirates designated RHP Phil Irwin for assignment. ... Nationals 1B Adam LaRoche went 0 for 2 in a rehab start for Class A Potomac on Thursday night. LaRoche has been on the disabled list since May 10 with a strained right quadriceps. LaRoche is eligible to come off the DL on Sunday. ... The series continues Friday night when Washington's Jordan Zimmerman (3-1, 3.70 ERA) faces Pittsburgh's Charlie Morton (0-6, 3.45).
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