Left-hander Marco Gonzales (1-0) limited the Giants to three runs in 6 1/3 innings, helping the Mariners win for the third time in four games this season.

Joe Panik hit his third home run of the season, a solo shot, and Evan Longoria added a two-run homer in his home debut for the Giants. San Francisco lost for the third straight time after a pair of 1-0 road wins against the Los Angeles Dodgers to open the year.

Giants left-hander Ty Blach (1-1), who pitched the first five innings of the 1-0 Opening Day win over Clayton Kershaw and the Dodgers, got into immediate trouble in the first when Dee Gordon beat out an infield single to shortstop and Jean Segura bunted for a hit.

After Robinson Cano drew a walk to load the bases, Haniger was rewarded for hitting Seattle's first ball to the outfield, a two-run single that scored Gordon and Segura.

Kyle Seager and Ryon Healy followed with RBI singles, putting the Giants in a 4-0 hole before they batted.

Panik's homer got San Francisco within 4-1 in the fourth. Cano added an RBI double and Guillermo Heredia a sacrifice fly in the fifth, creating a five-run difference and ending Blach's day.

Blach allowed six runs on 10 hits in 4 1/3 innings. He walked two and struck out two.

Longoria's homer in the seventh, his first of the season, cut the Seattle lead to 6-3 and finished Gonzalez, who allowed six hits, struck out two and did not walk a batter.

Austin Jackson's sacrifice fly made it a 6-4 game in the eighth off the third Mariners pitcher, Juan Nicasio, but the veteran stranded the potential tying runs on base when he retired Andrew McCutchen and Buster Posey.

Closer Edwin Diaz pitched a 1-2-3 ninth, striking out a pair, for his third save.

Gordon and Segura had three hits apiece for the Mariners, who out-hit the Giants 12-9. Seager went 2-for-4.

Panik, who became the first player in major league history to provide his team's first three runs of a season with three solo homers, collected two hits.

--Field Level Media