If the Baltimore Orioles were looking tonight for a last-minute reason to keep left-handed reliever Arthur Rhodes, they did not get it. If another team was looking for a last-minute justification for sacrificing a piece of their future to acquire him, they did not get it, either.

Rhodes, in what may have been his final performance as an Oriole, gave up a grand slam to Alex Rodriguez and a solo home run to Jay Buhner, sending the Orioles to a 7-4 loss to the Seattle Mariners in front of a sellout crowd of 44,931 at Safeco Field.

Rhodes, whose earned run average ballooned to 6.44, remains the Oriole most likely to be traded before Saturday's midnight deadline. Trades may still be made after the deadline, but players involved must first pass through waivers. With little hope of agreeing to a long-term contract extention, the Orioles informed Rhodes on Wednesday they would trade him, baseball sources said.

"If it was my last time [with the Orioles], I'll move on," Rhodes said. "If not, I'm still here and I still have to throw the ball."

Orioles third baseman Cal Ripken failed to hit his 400th home run, but he went 2 for 4 with a double, moving him past Sam Crawford into 25th place on the all-time hits list, with 2,966.

Orioles starter Jason Johnson (2-5) took the loss because three of the runs that came home on Rodriguez's grand slam belonged to him. Johnson, who had pitched at least six innings in four of his previous five starts, lasted just four-plus innings, allowing four earned runs.

"I just didn't go after them," Johnson said. "It's my own fault. . . . I didn't understand why I was taken out. But it was the manager's decision. I can't do anything about that."

"He lost a little control of himself out there," Orioles Manager Ray Miller said. "He tried to overthrow a little bit, but I have patience with that because Jason is going to be a good major league pitcher."

Johnson breezed through the Mariners' imposing lineup his first time through the order. Through the first three innings, he held the Mariners to two bloop hits, while striking out Ken Griffey, Rodriguez and Buhner. Orioles right fielder Albert Belle helped Johnson with a leaping catch at the wall in the second to take away an extra-base hit from Edgar Martinez.

Johnson took a 2-0 lead into the bottom of the fifth, but lost the shutout, the lead and the ball. And like so many such instances in the Orioles' trying season, the downfall began with wildness. Johnson opened the inning by walking No. 8 hitter Russ Davis and hitting No. 9 batter Dan Wilson.

Expecting leadoff hitter Brian Hunter to bunt, the Orioles put on the aggressive "wheel" play -- with Ripken charging from third and shortstop Mike Bordick running ahead of Davis to cover third base. However, after Johnson went to a 2-1 count on Hunter, the Orioles took off the wheel play. And it became crucial.

With Ripken now hanging back to cover third, Johnson had to field Hunter's perfect bunt down the third-base line. Johnson not only failed to get Hunter at first, he threw wildly past Will Clark, allowing Davis to score. When Johnson walked David Bell to load the bases with nobody out and Griffey coming to bat, it was the end of his night.

Rhodes came in and struck out Griffey. But Rodriguez yanked a fastball down the left field line for the fifth grand slam of his career. Catcher Charles Johnson set up off the inside corner on the 2-2 pitch, but Rhodes's offering caught the inside half of the plate, and Rodriguez turned on it.

After Martinez flied out to right, Rhodes began walking to the dugout, believing there were three outs. It was wishful thinking. There were only two, and the next batter, Buhner, launched a solo homer to right-center, stretching the Mariners' lead to 6-2.

Safeco Field isn't thought to be nearly as homer-happy as the Mariners' former home across the street, the Kingdome. But there was never any doubt about these two homers. Rhodes's ratio of one home run allowed every 4.8 innings is the second-worst on the Orioles, behind Jesse Orosco (one every 4.5 innings).

The six-run fifth inning made a winner out of Mariners starter Gil Meche (2-1), who was making his fourth career major league start.

Through the first four innings, Meche was nearly unhittable. Before Clark led off the fifth with a lined single to right, Meche had held the Orioles to one hit -- Harold Baines's dribbler up the middle in the second.

Charles Johnson broke open a scoreless tie with one out in the bottom of the fifth with a two-run double off Meche over the head of Griffey in center field.

An error by Griffey on Ripken's single to center with two outs in the eighth allowed Belle to score from second, pulling the Orioles to within 6-4 and putting the potential tying runs on base. But with Brady Anderson (sore ankle) apparently unavailable, Miller was forced to stay with Rich Amaral against Mariners right-hander Jose Paniagua, and Amaral struck out looking.