SEATTLE (AP) -- While Seattle's Felix Hernandez continued ringing up strikeouts with his fastball snapping in the high 90s, Oakland's Joe Blanton plodded along, quietly putting together solid innings without any flash.
Blanton's workman effort was rewarded in the end, and the Athletics now head south for a key series with the Los Angeles Angels, surprisingly on top of the AL West.
Blanton pitched seven solid innings, long enough for Oakland's offense to score four times in the eighth inning off Hernandez, rallying for a 4-2 win over the Mariners on Sunday.
"It's so encouraging for the guys to keep fighting to the end and to come back and win that game," Oakland manager Bob Geren said. "That was huge for the team and the confidence of all the players."
Hernandez, Seattle's young star, was cruising through seven innings, striking out a season-high 10 and allowing just four hits. It seemed only a formality that he would get through the eighth and likely turn the ninth over to closer J.J. Putz.
Daric Barton worked a nine-pitch walk off Hernandez and Brown, second in the American League now with 22 RBIs, dumped a single into left field, scoring Hannahan and Ellis, and bringing Hernandez's day to an abrupt end.
"I want to drive them in, that's the biggest thing," Brown said. "I wanted to drive those guys in and having the right mentality when I'm up there in those situations helps."
Brandon Morrow entered for Seattle and continued the trend, walking Frank Thomas on a 3-2 pitch. Cust, who struggled in the field with a pair of deep fly balls and struck out twice, lined a single into right to score Barton, giving Oakland its first lead. Sweeney then capped the rally, lining a single into left past a diving Adrian Beltre to score Brown. Sean Green finally got Seattle out of the inning with a strikeout of Hannahan.
Hernandez (2-1) ended up allowing four runs on six hits, but lost for the first time in his last seven decisions.
"Everything was working the whole game," Hernandez said. "Those guys made adjustments. Like I say, it was a tough loss."
The rally made Blanton (2-4) a surprise winner, after trailing all day but managing to keep the A's close long enough for their offense to show up. Blanton went seven innings, giving up two runs on eight hits and striking out three.
Blanton pitched at least seven innings for the fourth consecutive start, but won for the first time since April 11 at Cleveland. He's now 5-0 in his career at Safeco Field.
"If the runs aren't coming, I feel like if we stay in the game, and keep giving the team a chance, they'll come around eventually," Blanton said.
Huston Street pitched the ninth for his eighth save in nine opportunities. He also got the save Friday night as Oakland took two of three from its AL West rival.
Meanwhile, Seattle slipped further back in the AL West, dropping four of six on its homestand and now heads out on a difficult six-game road trip to Cleveland and New York.
"There are some positives, but we are still not running on all cylinders," Seattle manager John McLaren said. "Too many guys [are] not swinging the bat well, not driving in runs when they are out there."
Otherwise, Seattle missed out on scoring opportunities in the second and sixth, when Brad Wilkerson doubled and Kenji Johjima singled with one out, putting runners on first and third. Betancourt grounded into a double play that ended the inning.
Oakland threatened in the fourth, loading the bases on singles by Ellis, Brown and a 20-foot broken-bat infield single from Thomas, where the barrel of the bat ended up in shallow left.
Hernandez got Cust swinging at a 1-2 fastball, then induced Crosby's slow chopper to third, where Beltre fielded the grounder on the bag to end the inning.
Rain suddenly started falling in the bottom of the seventh with the Safeco Field roof open. The roof didn't completely close until three batters into the top of the eighth. ... Johjima had to get a new catching helmet in the fifth when a chunk of his broke off after Ellis' follow through caught the brim of Johjima's helmet.