HOUSTON -- The Houston Astros expected more from Mike Lamb than he showed the first two months of the season.
On Sunday he exceeded those expectations, hitting a grand slam and driving in five runs as the Astros beat the Seattle Mariners 10-3 to complete a three-game sweep.
Lamb was exceptional throughout the weekend series, going 8-for-10 with two homers, eight RBI and three doubles. He has 12 RBI in June after managing just five in April and May combined.
"He's coming on like we feel like he can. He won't hit like this every game, but I expect it like this on most games," Astros manager Phil Garner said, only half-joking.
On Sunday Lamb helped pick up the slack for Houston, which was playing without All-Star Lance Berkman, out with flulike symptoms.
His grand slam into the bullpen came in the first inning and gave starter Roy Oswalt (7-4) some breathing room to pick up his first win since May 12. He'd had two losses and four no decisions in that span.
"It's been tough," Oswalt said. "Hopefully we can get everything rolling from here."
Oswalt wasn't sharp, allowing a season-high 12 hits but giving up just three runs. He had reached 114 pitches when he was chased on an RBI-single by Jose Vidro with two outs in the sixth. Trever Miller struck out Raul Ibanez to end the inning.
Oswalt struck out six and walked two in his shortest outing since going five innings on April 13.
Houston's ace now has 105 wins since 2001, which ties Randy Johnson for most wins in the majors in that span.
The sweep is Houston's first in a three game series this season. The Astros swept two consecutive two-game series' from April 16-19.
"Offensively, every inning we had pressure on the other team," Lamb said. "We had guys on base and had good at-bats. It didn't seem like we had any easy innings. That's key when you're facing pitching staffs like we have been."
The Mariners have lost five straight since a season-high five game winning streak.
Ichiro Suzuki seemed especially frustrated by Seattle's recent skid.
"It's like a comedy of errors," he said. "But for us, it's not funny."
Houston extended its lead on a two-run bloop single by Mark Loretta in the second inning. Vidro doubled in the third and scored on a single by Richie Sexson that made it 6-2.
Morgan Ensberg reached when shortstop Yuniesky Betancourt couldn't handle his grounder in the third. Lamb's double scored Ensberg and pushed Houston's lead to 7-2.
"The balls are falling," Lamb said. "I've been getting better pitches to hit, that's for sure. I always think that I'm a decent hitter, but I need pitches to hit to be successful."
Jarrod Washburn (5-6) lasted just three innings in his shortest start of the season. The lefty allowed a season-high seven runs and six hits with three walks.
"It's just a struggle so far for me," Washburn said. "The last month I threw the ball well, right now my command just isn't there. It's what's leading to all the problems."
Seattle manager Mike Hargrove agreed.
"He's not pitching like he can," Hargrove said. "He'd be the first to tell you that. He started out the first hitter like he was fine, and all of a sudden he fell behind a lot of guys and gave up the grand slam."
A single by Suzuki drove in Sexson in the second inning to make it 4-1. Suzuki had four hits on Sunday and extended his hitting streak to 12 games. Seattle almost added another run, but Ben Broussard couldn't beat rookie Hunter Pence's throw home.
Pinch hitter Orlando Palmeiro had a run-scoring single in the eighth for Houston. Pence hit a hard grounder down the left-field line to drive in two more runs later in the inning.
Several players on both teams wore light blue wristbands on Sunday to raise awareness of prostate cancer. ... Sunday was Oswalt's second career start against Seattle after receiving a no-decision in his meeting with the Mariners in 2002.