Milwaukee, WI -- (Sports Network) - Josh Willingham became the 13th player in Major League Baseball history to hit two grand slams in one game, powering the Nationals to a rare 14-6 rout of the Milwaukee Brewers.

Willingham added a double during his career night, while Nyjer Morgan was the catalyst at the top of the order, going 3-for-5 with two runs scored, an RBI and a stolen base for Washington, which has scored 30 runs over a three-game winning streak.

Cristian Guzman and Adam Dunn each had two hits, two runs scored and two RBI, while Ryan Zimmerman hit a solo homer and scored three times in the lopsided affair.

Jason Bergmann (1-1) was credited with the win in relief behind rookie Craig Stammen, who yielded five runs on nine hits through 4 2/3 frames.

Jeff Suppan (5-8) continued his dismal performance on the mound for Milwaukee, getting tagged for 10 runs on 10 hits and four walks in 5 1/3 frames.

Ryan Braun went 3-for-4 with a two-run homer, and Corey Hart added a solo shot for the struggling Brewers, who fell below .500 (49-50) with their sixth loss in eight games.

After Milwaukee cut its deficit to 6-5 with a three-run fifth, the Nationals put up seven runs in their next turn at the plate.

Guzman roped a two-run double, and Suppan was mercifully pulled after walking Zimmerman with one out. Mitch Stetter entered and gave up an RBI double to Dunn before exiting after a walk to Nick Johnson.

Willingham then greeted Mark DiFelice with his memorable grand slam -- the fourth of his career -- breaking the game wide open.

Jody Gerut recorded a pinch-hit, RBI double in the sixth for Milwaukee, and Zimmerman joined the home-run party with a leadoff round-tripper in the eighth to account for the final margin.

Prince Fielder's RBI double in the first and Hart's leadoff blast in the second staked the hosts to a 2-0 lead.

But Washington, which stranded a runner in scoring position in each of the first four innings, woke up with a six-run fifth frame.

Alberto Gonzalez led off with a double and scored on Morgan's single two batters later. A single and walk loaded the bases for Dunn, who earned a free pass to force in another run. Suppan managed to strike out Johnson, though Willingham took the first pitch he saw over the left-field fence for a 6-2 Washington edge.

Milwaukee made it a one-run game in the home half, as Felipe Lopez drove in Jason Kendall with a single and later scored on Braun's 20th homer of the season.

Game Notes

The 13 runs were a season-high for the Nationals...Boston's Bill Mueller was the last to hit two grand slams in one game back on July 29, 2003...Suppan, who came in with a woeful 6.12 earned-run average in eight starts at home this season, is 0-4 in eight starts since a June 12 defeat of the Chicago White Sox...Lopez had three hits for Milwaukee.