Baltimore's Wei-Yin Chen stared into left field with a look of disbelief.
Even though Henry Blanco's two-run home run had already disappeared into the sea of orange shirts in the left-field seats, Chen's arms remained at his side and eyes still peering into the crowd after Blanco drove his 0-2 fastball out of the park for a go-ahead, two-run home run with two outs.
Blanco's home run was the difference that lifted the Mariners to a 3-2 win in the rubber match of a three-game series.
"At this point you just want to contribute to win games and hope for the best," Blanco said.
Joe Saunders (10-10) picked up the win to snap a two-game skid. The lefty allowed runners in scoring position in each of his first five innings and the leadoff man to reach base in five of his six frames, but held Baltimore to two runs on eight hits, two walks and a hit batsman.
Raul Ibanez had two hits including an RBI double for Seattle, which won its second straight game.
Danny Valencia, who was recalled from Triple-A Norfolk prior to the game, blasted a two-run home run for the Orioles.
Chen (6-4) saw his four-decision winning streak end. He gave up three runs on five hits and three walks in seven innings.
"Wei-Yin was really good again," Orioles manager Buck Showalter said of his starter. "That was frustrating for everyone to not be able to build when we had a lot of people out there."
Seattle took the lead in the second inning. Michael Morse and Ibanez picked up back-to-back doubles to start the frame and put the game's first run on the board.
Baltimore stranded eight runners on base in the first five innings, but finally broke through in the sixth inning.
Steve Pearce worked a leadoff walk and Valencia followed with a long home run to left-center field to put Baltimore on top, 2-1.
Seattle quickly regained the lead in the seventh inning.
Brendan Ryan worked a two-out walk and Blanco crushed a low, inside fastball into the left-field seats to give Seattle a 3-2 lead.
Yoervis Medina fanned four over two perfect innings in the seventh and eighth innings before Danny Farquhar retired the Orioles in order in the ninth to earn his second save of the season.
Baltimore was 0-for-11 with runners in scoring position and stranded eight on base and the Mariners were 2-for-6 with runners in scoring position and left five on base ... The Mariners are 6-2-1 in their last nine series since July 1 ... Seattle leads the American League with 46 home runs in the seventh inning or later ... Saunders is 7-0 in nine career starts against Baltimore ... The Orioles fell to 10-6 in rubber matches this season and 19-11 against the AL West.