SEATTLE -- Bob Geren should have known this was coming.
Oakland's new manager probably should have foreseen well before late Wednesday night that his players would drench him in a postgame shower of beer and every other liquid they could find to celebrate his first win as a major league manager.
After all, Rich Harden was pitching.
Seattle's nightmare allowed just three singles and struck out seven in seven innings while No. 9 hitter Mark Ellis had five RBI to lead the Athletics to their first win of the season, 9-0 over the Mariners.
"Tremendous performance," a soaked, foul-smelling Geren said after his players ambushed him in the clubhouse hallway following the return to dominance of Harden, who missed most of last season with back and elbow problems before he lost Game 3 of the ALCS to Detroit.
"He looks great," Geren said. "I'm very thrilled."
The Mariners absolutely were not.
The runaway night was more reminiscent of last season, when Oakland went 17-2 against Seattle, than the previous two games. The Mariners were emphatically denied their first 3-0 start in 12 years, while the A's avoided their first 0-3 start since 1996.
It was also very reminiscent of how Harden masters the M's -- and many others.
"Unbelievable," Ellis said of his ace, shaking his head. "I don't want to jinx him or anything, but everyone knows how well he pitches. To make good hitters look as bad as he does is a credit to how good he is."
Especially against Seattle. Harden has allowed seven earned runs in 10 career games against the Mariners. That's an ERA of 1.28. He's 5-0 with a 0.86 ERA in six starts at Safeco Field, which is a few hours drive and a ferry ride from his native Victoria, British Columbia.
"I just love coming up here, pitching in that cool weather," said Harden, who had about a dozen family members watching his latest domination of his region's team.
"I'm wanting to put last year behind me, take the focus off that. Hopefully, now I'll stop getting asked that question."
Not hopefully. Likely. Wednesday showed why the A's have won 11 consecutive regular-season games started by Harden since Aug. 14, 2005, against Minnesota. He's 6-0 in those starts. Of course, the 25-year-old Canadian pitched in just nine games during 2006 because of a strained back and a sprained elbow.
But those pains looked light years ago Wednesday.
Harden (1-0) continually and easily fired fastballs past the flailing Mariners. His split-fingered pitches danced and darted. His changeups were often unfair.
He didn't allow a hit until Ichiro Suzuki's single leading off the fourth, on a splitter in the dirt that Harden said he's never seen a batter hit. He had only two three-ball counts - on both of his walks, to Jose Vidro in the fourth and Suzuki in the sixth. Geren gave him a hearty handshake for a job well done in the dugout after the bottom of the seventh.
"He knew what he was doing against everybody out there," Vidro said.
Conversely, how miserable was Miguel Batista's 4 2/3-inning Mariners debut? Eight runs allowed. Ten hits. Two balks. Dodging of line drives hit right at him -- plus one he didn't dodge that stung his left foot. He continually turned to watch drives bang off outfield walls. And he backed up home plate seven times as runners scored.
The one time he didn't backup home, Mike Piazza scored on Batista's first balk. The 36-year-old former Diamondback started and then stopped his throwing motion during Oakland's five-run second inning.
Piazza had reached on a single to lead off the decisive inning, his first hit as an AL player after seven at-bats. Eric Chavez then doubled before Batista's 0-2 pitch to Bobby Crosby grazed Crosby's jersey. Batista followed that gaffe by walking rookie Travis Buck to load the bases for Ellis.
Two pitches later, Ellis drove a thigh-high fastball to the wall in left-center field to score all three runners and put Oakland ahead 4-0. Milton Bradley's single then scored Ellis to make it 5-0.
Bradley added an RBI double in the fourth. Ellis then tied his career high with his fourth and fifth RBI with another ringing double in the fifth inning, on Batista's final pitch.
"There is no excuse. I just didn't get my job done. That is the reason we lost," Batista said.
- Sean White relieved Batista for his major league debut -- and hit Shannon Stewart with a pitch. Stewart tacked on a ninth run on Nick Swisher's single.
- Buck, a native of Richland, Wash., playing in his second game in front of family, struck out three times.
- The Mariners gave SS Yuniesky Betancourt a three-year contract extension, with a club option for 2012, one day after he hit the tiebreaking home run late in an 8-4 win.