He's not one to give up free passes.
Milone (12-10) allowed eight hits and two runs, matched a career high with 10 strikeouts and had no walks.
He has walked one or no batters in each of his past 14 starts. That ties the longest streak by a starter in Oakland history. Gil Heredia also had 14 starts with one walk or less from May 29 to Aug. 11, 1999.
During his stretch, Milone has issued just eight walks and struck out 78 in 88 innings. His 12 wins also ties the Oakland rookie record set by Chris Codiroli in 1983 and matched by Joe Blanton in 2005.
"I've always been a strike-thrower," Milone said. "I feel like nothing good comes from putting guys on base with a free pass. That's probably the reason why I give up so many hits."
The Mariners did pound out eight hits but couldn't bunch enough together.
"That's part of what he does. That's one of his strengths, making you hit your way on," A's manager Bob Melvin said. "He has given up his share of hits but a lot of times they're the other way. He makes better pitches when guys are on base, when he has to."
Grant Balfour worked the ninth to pick up his 16th save in 18 opportunities.
The victory moved the A's within 3½ games of Texas in the AL West after the Rangers lost to Tampa Bay 6-0. Oakland is also battling the New York Yankees and Baltimore atop the wild-card race.
"We're getting our hits but we're not doing any damage with them," Mariners manager Eric Wedge said, "whether it's stringing hits together or extra-base hits."
Oakland was coming off a three-game sweep at home by AL West-rival Los Angeles as well as the trauma of watching right-hander Brandon McCarthy get hit in the head by a line drive. He remained behind, still in stable condition after brain surgery.
"I don't think you have to do a character check on this team anymore," said Gomes, who hit his 16th home run in the fifth. "We got it figured out. We've gone through some adversity with injuries, some adversity with key guys getting send out or traded, issues with (Bartolo) Colon (50-game suspension for PEDs). These guys are doing a good job just keeping our heads down and going to battle with 25 guys in the clubhouse."
Jason Vargas (14-10) allowed just four hits and three runs in seven innings for Seattle. He walked three and struck out six. His critical mistake was a 1-1 pitch to Gomes. Adam Rosales and Coco Crisp both had singled with two outs. Gomes then turned on the inside fastball and hit it against the left-field facade for a 3-0 lead.
"I was trying to go about his bat and his hands and he was able to stay on it," Vargas said. "The pitches that I was worried about were to the two batters before that when I let them extend it."
His frustration goes back to his 2-2 count to Rosales, the ninth hitter. Rosales had fouled off two pitches then slapped a curveball to center.
"It's frustrating when the inning extends and ends how it did," Vargas said. "I feel like I am more than capable of getting him out with my other two pitches."
Vargas has yielded 32 home runs this season, including six in his last three starts.
Kyle Seager made it 3-2 in the sixth with a leadoff home run, his 17th. It came on off a 1-1 curveball from Milone, who had a career-low three-inning outing in his previous start Monday against the Angels.
The A's now head to L.A. for a four-game showdown with the Angels.
"It gives us momentum going into their place," Milone said of the sweep.
A's starter Brett Anderson is 14 months removed from Tommy John surgery but there is no talk yet of a possible innings restriction next season, much like Washington did with Stephen Strasburg. "It could be something we discuss but it's not on the radar yet," Melvin said. "Maybe the fact that he is pitching for a month and a half this year will have something to do with next year." ... The A's said there is nothing new to report on the condition of RHP Brandon McCarthy, still in a Bay Area hospital after being hit in the head by a line drive last Wednesday. ... Felix Hernandez (4.2 IP) and Hisashi Iwakuma (3.2 IP) failed to go at least five innings in back-to-back games in the first two games of this series. It's the first time since June 19-20 that a Mariners starter did not last at least five innings in consecutive games.