The 7-4 defeat sent Pittsburgh to its seventh loss in eight games.
PITTSBURGH (AP) -- Frank Robinson felt so comfortable with Livan Hernandez on the mound, he took a night off from managing the first-place Nationals and watched in street clothes as his staff ace kept a two-month winning streak going.
Hernandez got plenty of help from his defense in winning his ninth consecutive decision, and Jose Guillen homered twice as Washington built a five-run lead and went on to beat the Pittsburgh Pirates 7-4 Monday night.
Guillen, Cristian Guzman and Brad Wilkerson drove in two runs each as the NL East leaders won their 17th in 21 games and improved to 4-3 on a circuitous road trip that has taken them from Anaheim to Texas to Pittsburgh in a week's time.
The Pirates have dropped seven of eight since winning a season-high four in a row and are six games under .500 after being 30-30 on June 11.
Served one-game suspension
Robinson wisely chose Monday to serve his one-game suspension for his June 14 shouting match with Angels manager Mike Scioscia, letting bench coach Eddie Rodriguez run a game that Hernandez controlled until a three-run seventh inning.
Washington is 13-3 when Hernandez starts and he hasn't lost in 12 starts since April 19.
"It makes it a little easier when Livan Hernandez is on the mound, and when you score runs, it makes it easier," said Robinson, whose appeal of his suspension was denied earlier Monday.
"But in the end, when it got a little tight, he [Rodriguez] made the right moves."
Robinson didn't watch from the clubhouse or use a messenger to relay strategy to the dugout as some managers do while suspended, but watched from the stands just like a fan.
"I just tried to sit back and enjoy the game," Robinson said.
Guillen has big game
Guillen, cast off by the Pirates five years ago, helped his manager do that with solo homers in the first and fifth.
Guzman added a two-run double that made it 3-1 in the second against Mark Redman (4-5).
Wilkerson contributed a two-run, opposite-field single to left field in the fourth, giving him six RBIs in two games following a 1-for-15 slump.
Despite the bad inning, Hernandez (10-2) outpitched Redman in a matchup of two of the NL's top starters this season, coaxing the Pirates into four double-play grounders in the first six innings. He had been 0-2 in Pittsburgh and was 2-3 with a 5.49 ERA against the Pirates.
"He's the type of pitcher you've got to try to base-hit to death," the Pirates' Daryle Ward said.
"When you get singles you've got to keep them going and keep him throwing from the stretch and get him frustrated, but he looked comfortable most of the night."
Lifted after seven innings
Hernandez was lifted after throwing 107 pitches in seven innings, giving up four runs -- two earned -- and eight hits, including Jack Wilson's two-run single in the seventh. Gary Majewski pitched the eighth and Chad Cordero finished up in the ninth for his 19th consecutive save and 22nd of the season.
Redman, the Pirates' most consistent starter, began the game with a 2.80 ERA before allowing six runs and 10 hits in his second-worst start this season. Despite not being sharp -- he gave up leadoff hits in four innings -- he managed to last seven innings a day after Pirates starter Kip Wells couldn't make it out of the fourth in an 8-0 loss in Boston.
"I was struggling and my stuff wasn't working," Redman said. "You can't keep leaving fastballs up to a fastball hitter like Guillen."
Redman had allowed only six runs in his last four starts since giving up six runs and seven hits in four innings in his worst outing this season, an 11-5 loss in St. Louis on May 25.