SEATTLE — Erik Bedard got his first major league win, and Melvin Mora hit an RBI double in the Baltimore Orioles’ 5-2 victory over the Seattle Mariners on Wednesday night.

Jay Gibbons homered in a three-run seventh, and Luis Matos also connected for Baltimore.

The Orioles won for the second straight night at Safeco Field, where they are 4-19 since the ballpark opened in July 1999. They also beat the Mariners for the fourth time in five games this season.

The last-place Mariners lost for the ninth time in 10 games and fell 13 games under .500 for the first time since Sept. 12, 1998.

Bedard (1-1), a 25-year-old left-hander making his sixth career start, pitched 6 2/3 innings. He gave up two runs on four hits and four walks, striking out seven.

Mora, leading the A.L. with a .383 batting average, went 2-for-3 with two doubles.

Jerry Hairston opened the sixth with a single and scored on Mora’s double over third base off Ryan Franklin (2-4) for a 1-0 lead.

Baltimore scored three runs on four straight hits off Franklin in the seventh to make it 4-0. Gibbons hit his fifth homer, Matos and Larry Bigbie followed with doubles for another run, and Hairston added an RBI single to chase Franklin.

The Mariners ruined Bedard’s shutout bid in the seventh on Rich Aurilia’s RBI double. Jolbert Cabrera’s infield single off Mike DeJean drove in Aurilia for Seattle’s second run, but DeJean struck out Edgar Martinez with the bases loaded to end the threat.

Matos homered off Eddie Guardado in the ninth, and Jorge Julio got three outs for his seventh save in eight chances. He struck out Martinez with two on to end it.

Franklin pitched 6 1/3 innings, allowing four runs and nine hits.

Lineup could become crapshoot

When he was manager of the Oakland A’s and his team was immersed in a slump, Billy Martin made up a lineup by picking the order of the players out of his hat.

Mariners manager Bob Melvin said he isn’t to that point in trying to find a productive lineup, but he’s not beyond trying something new.

On Wednesday, Melvin used his 33rd different lineup in the team’s 39th game.

Some of the switches have been because of injuries and players needing days off, but many have been made in attempt to snap the Mariners from their hitting funk.

The Mariners are averaging 4.1 runs per game. They are last in the American League in home runs (26) and next-to-last in on-base percentage (.323).

“You know, I was criticized quite often last year about running the same group out there in the same spots and I felt good about the guys that we had,” Melvin said. “It didn’t work there in the second half of the season and you have to make some adjustments and get the best combinations that you can.

“Predominantly, we’re running the same group of guys out there; we’re tweaking with a couple of different spots.”

The second spot in the order has been manned by Randy Winn, Rich Aurilia, Scott Spiezio and even John Olerud.

On Wednesday, Jolbert Cabrera started at first base and hit second for the second time this season. Olerud (second, third, fifth, sixth, seventh and eighth) and Aurilia (second, fifth-through-ninth) have hit in six different spots. Both said it doesn’t really matter where you hit in the lineup, although consistency is nice.

They said it’s not a surprise that Melvin has used so many different lineups, given the team’s troubles at the plate.

“I’ve seen it on teams that are succeeding and they start changing things and you’re going, ‘Why are we changing it?’ ” Aurilia said. “You understand it a little bit more when you’re losing and you’re trying to find the right combination.

“I think we’re all veteran guys in here and we understand that’s what he’s trying to do.”

Melvin opted to start Cabrera over Olerud with Baltimore sending left-hander Eric Bedard to the mound.

Olerud is mired in a 3-for-18 slump that has dropped his average to .238. He hasn’t had an RBI since getting three on May 2 against Detroit.

Olrerud perplexed by slump

Olerud said he is surprised by his — and the team’s — slump.

He said he’s been watching videotape, even going as far back as the 1993 season when he hit an American League-leading .363 with the Toronto Blue Jays.

In batting practice sessions, Melvin said Olerud looks fine. But, like many of his teammates, it’s not carrying over into the game.

“Maybe I’m a little too much of an optimist, but I do have a good feeling when he goes out there,” Melvin said. “We’re not getting the results right now but I think we will.”