George Kottaras hit a three-run homer as the Oakland Athletics downed the Seattle Mariners, 6-1, in the first of three games at Safeco Field.
Josh Donaldson and Stephen Drew also knocked in a run for Oakland, which snapped a three-game slide and remains a game ahead of the Tampa Bay Rays for an AL wild card spot.
A.J. Griffin (5-0) allowed a run on six hits and a walk while striking out seven over 5 1/3 innings to become the first pitcher in Oakland history to begin his career 5-0 as a starter.
Felix Hernandez (13-7) was touched for six runs -- five earned -- on 11 hits and a walk over 4 2/3 innings for the Mariners, who have lost two of three.
Oakland struck in its first at-bat when Seth Smith hit a one-out single and rounded the bases two batters later on a Yoenis Cespedes bloop single to right field that skipped past Eric Thames' glove.
Seattle, though, answered with a run in the second inning after Michael Saunders hit a leadoff single, moved to second on Luis Antonio Jimenez's two- out walk and came home on Brendan Ryan's base hit to right field.
Kottaras then put Oakland back on top in the fourth inning with a three-run blast over the right-field wall. Donaldson walked and Drew singled prior to Kottaras' fourth homer of the year.
After Seattle left two on in the bottom of the fourth, the A's added a pair of runs in the fifth when Brandon Moss singled before coming home on Donaldson's double into the left-field corner. Drew plated Donaldson with a base hit to right field, giving Oakland a 6-1 lead and knocking Hernandez out of the game.
The Mariners only advanced one runner past second base for the remainder of the game.
The only other pitcher in Oakland history to start his career 5-0 was reliever Todd Burns in 1988 ... A's starting pitchers have now walked three batters or fewer in each of the last 36 games, which is the second longest streak in Oakland history. The longest is a 41-game streak from July 16-Aug. 28, 2001 ... The season series between the teams is tied, 7-7 ... Hernandez fell to 13-6 in 26 career starts against Oakland.