SEATTLE, AUG. 15 -- If there exists a better pitching staff in the mortal (non-Oakland) portion of the American League than these Seattle Mariners, the Baltimore Orioles don't want to know about it. And if there's any better fodder for their lively arms than the Orioles, the Mariners want to find it.

Randy Johnson tonight became the third straight Seattle starter to subdue Baltimore with relative ease, cruising to a complete-game four-hitter as the Mariners beat the Orioles here for a second straight day, this time by 2-0 before 15,308 in the Kingdome.

Each Seattle starter in this three-game series hurled the full nine innings, stretching the staff's remarkable string of working at least into the seventh inning to 33 times in 35 games. Johnson had few difficulties in improving to 11-7 with his second career shutout, as he allowed only one runner to reach third base.

He walked two and struck out nine -- including Mickey Tettleton three times, as Orioles designated hitter established a single-season team record with 126 whiffs.

The Mariners put 20 runners on base against starter Pete Harnisch (9-7) and three relievers, but scored only twice; they stranded a club-record 16 men. Alvin Davis provided both RBI with a third-inning sacrifice fly and fifth-inning home run. Each Mariners' starter except catcher Dave Valle had at least one hit.

"We have a pitching staff that's the envy of just about everyone in the league," Seattle Manager Jim Lefebvre said. "All we need to do is get them a few runs a night. That's been a struggle, as you can see."

The Orioles fell to 56-60 but remained seven games behind the Boston Red Sox in the AL East; they were 3-6 on this western road trip, losing two of three in each city, but dropped only two games in the standings. They'll gladly return tonight to Baltimore, where they will nurse their slew of nagging injuries and play 25 of their next 35 games.

Baltimore scored 28 runs on the road swing, but 11 of those came in one game versus the sagging Mark Langston and the California Angels. They were no match for the Mariners staff, off which they managed four runs and 15 hits in three games. They have one home run in 96 innings and have had seven extra-base hits in their past seven games to 26 for their opponents.

"Not to take anything away from Johnson, but we had a lot to do with this," Orioles Manager Frank Robinson said. "We're just not swinging the bats well. . . . Give {Harnisch} some credit. He gave us a chance to win the ballgame if we had done anything offensively."

The Mariners, fourth in the AL West beginning the day, improved to 60-58. They finished 6-7 on their longest homestand of the season and beat the Orioles for the sixth time in nine meetings.

The Orioles had battered Johnson throughout his brief Mariners tenure, entering tonight with a .302 batting average and almost 4.6 runs a game off him in three previous meetings. But that was before the gawky, 6-foot-10 left-hander became the potentially dominating force he is now.

"He has no idea how good a pitcher he can be," Lefebvre said. "He's had to struggle for two years just to be a halfway decent major league pitcher, so he has no concept that he can become a very good to great major league pitcher."

Johnson escaped a second-inning jam but otherwise breezed. His fastball was humming, and he showed surprising command and control of the change-up that has taken on added prominence in his repertoire in recent months.

"He was getting his first pitch over and throwing everything for strikes," Orioles center fielder Mike Devereaux said. "He's a different pitcher than when we've seen him before."

Johnson retired the Orioles in order five times, including four of the first five innings. The lone predicament came in the second, when a leadoff walk to Cal Ripken and Bob Melvin's double put runners at second and third with one out. But Johnson's fastball got a bit quicker, and he wriggled free by getting Craig Worthington on a popout and Chris Hoiles on strikes.

He saved a run in the fifth on an acrobatic fielding play. After walking Hoiles and Rene Gonzales with two out, he reached back to snare with his bare hand Dave Gallagher's bouncer that seemed headed to center field and turned it into an inning-ending groundout instead.

Harnisch, meanwhile, was struggling mightily. He threw 86 pitches and put 10 runners on base in the first four innings, but yielded just a single run.

Tonight was the 23-year-old's fourth try at becoming a 10-game winner, but it was an uphill battle from the start. He threw nine straight balls to begin the game.

"I thought I made some good pitches when I had to," said Harnisch, who has lost four of his past six decisions. "Usually when I'm wild, I'm wild high. Tonight I got the ball down, but it seemed like I was just missing by a few inches with each pitch and I was always behind."