WASHINGTON -- The sixth inning should have been over when Cristian Guzman hit a routine three-hopper to J.J. Hardy. All the shortstop had to do was field the ball, take a couple of steps to touch the bag and throw to first for the double play.

Instead, Hardy bobbled the ball. Everyone was safe, and the Washington Nationals capitalized with four unearned runs in Friday night's 5-1 victory over the Milwaukee Brewers.

"I just tried to be too quick," Hardy said. "I tried to turn it before I fielded it."

It was a simple mistake that turned the game. Washington sent six men to the plate after Hardy's bobble -- his fourth error of the season -- to break a 1-1 tie and make a hard-luck loser out of Brewers starter Jeff Suppan (2-4). Ryan Zimmerman drove in a run with a double, Lastings Milledge got an RBI grounder, and Jesus Flores doubled in two more as the Nationals took a series opener in which they accumulated a season-low three hits.

"That's the name of the game in baseball," Zimmerman said. "If you get opportunities like that, especially in the fifth inning and beyond, you have to take advantage of them."

Brian Sanches (1-0), promoted earlier in the day from Triple-A Columbus, made his Nationals debut by striking out the side while allowing one hit in the sixth. His one inning of work was enough to earn him his second major league victory -- the first came last year with the Philadelphia Phillies.

Saul Rivera, Luis Ayala and Jon Rauch each pitched an inning to finish the win. Nationals starter Odalis Perez threw five solid innings but has only a single victory - along with four losses -- to show for his 11 starts. Perez cut his thumb while throwing a curveball in the fourth inning but said he was fine.

Suppan had allowed only one hit -- Wily Mo Pena's first home run of the season -- through the first five innings but unraveled after Hardy's error. Even though the double play couldn't be assumed for statistical purposes, the inning unfolded in such a way that none of the runs were earned.

Thus, Suppan's unusual pitching line: 5 2/3 innings, three hits, five runs with only one earned, four strikeouts, three walks and a hit batter.

It's been that type of stretch for the Brewers, who have lost seven of nine.

"We've had our ups and downs," Suppan said.

Suppan also got his first base hit of the year. Batting in what has become the pitcher's customary No. 8 spot in manager Ned Yost's lineup, he tied the game in the fourth inning with a single that scored Hardy. Suppan had been 0-for-17.

Pena, part of a Nationals outfield corps that has been incredibly unproductive offensively, offered some rare pop from the bottom tier of the lineup with a line drive that sailed into the second row of the left-field bleachers in the second inning. It was his first homer since Sept. 12 of last season, a span of 144 at-bats.

"A lot of relief for him because everybody associates him with home runs, he's so big and so strong," manager Manny Acta said. "And the fact that he hadn't hit one yet, he took a lot of weight off his shoulders."

The hit also doubled the home run output of the three outfielders who started the game for the Nationals. Milledge has one home run, while Elijah Dukes (0-for-2) has none to go with his average of .063.

Dukes fouled a pitch off the top of his foot in the fifth inning, causing a bruise the forced him to leave the game in the sixth. X-rays were negative, and he is day-to-day.

Notes

• Hardy's stolen base was his first of the season.
• Nationals third-base coach Tim Tolman took the night off to go to Tucson, Ariz., to celebrate this son's high school graduation. Double-A Harrisburg manager John Stearns coached third in Tolman's place.
• Brewers right-hander Tim Dillard, promoted from Triple-A Nashville earlier in the day, pitched a scoreless eighth inning in his major league debut.