OAKLAND -- In what was easily his best start of the season, Marco Gonzales only had one skittish inning when he had to pitch through traffic. Even then, the Mariners left-hander deftly worked his way out of trouble with relative ease.
Gonzales pitched a career-best seven scoreless innings and the Mariners made an unearned run in the fourth inning hold up in a 1-0 win over the A's at the Coliseum on Wednesday.
Guillermo Heredia doubled and scored the game's lone run, helping the Mariners extend their longest winning streak of the season to five games. Seattle managed only six hits and went 0-for-9 with runners in scoring position, but it rode the pitching of Gonzales and two relievers to the team's fourth shutout victory of the season.
"Can't be any more proud and happy for him, kind of taking the next step, being consistent and using all of his pitches," Mariners manager Scott Servais said of Gonzales. "When you have all three working, locating the fastball, really good changeup and the curveball's been such a vital pitch for him, you really see this guy stepping forward. We needed everything he gave us."
Gonzales (4-3) had never pitched more than 6 1/3 innings, but he was masterful against the A's. He retired nine of the first 10 batters, then sat down 12 of the final 13 he faced after issuing back-to-back walks to open the fourth.

"I think it had bits and pieces of some of my best stuff," Gonzales said. "I really was just trying to get ahead of hitters, get myself into good counts and allow my pitches to play. I think I'm really starting to figure out how my repertoire works, and my best chance is when I'm ahead in the count."
The left-hander struck out six and worked out of the jam in the fourth by getting Matt Chapman to line out, fanning Mark Canha and getting Matt Olson to fly out to left.
"It's a step up," Gonzales said. "I try to take positives from every time out there and learn from it. But those situations where you're in traffic, especially to start the inning, just says something about the communication that [catcher Mike Zunino] and I have behind the plate, the trust he has in me to be able to throw pitches behind in the count and to get timely ground balls."

Juan Nicasio pitched the eighth and Edwin Diaz struck out the side in a perfect ninth for his 17th save, tied for the Major League lead with Colorado's Wade Davis.
Seattle needed the strong pitching performance to offset a stellar outing by Oakland starter Daniel Gossett (0-2), who allowed one unearned run on four hits over seven innings with five strikeouts.
A day after driving in Jean Segura for the go-ahead run in a 10-inning win, Heredia scored the Mariners' only run after doubling to lead off the fourth. Heredia took third on Nelson Cruz's flyout to right, then scored when A's shortstop Marcus Semien -- playing in -- bobbled Kyle Seager's grounder for an error.

MOMENT THAT MATTERED
Got his first: Making his Major League debut, Mariners right fielder John Andreoli singled off Gossett with one out in the fifth for his first career hit. Andreoli was called up from Triple-A Tacoma earlier in the day and started in place of Mitch Haniger, who is nursing a sore right wrist. Andreoli also made a sliding catch in right-center field to rob Jonathan Lucroy of a hit in the eighth.
"It was unbelievable," Andreoli said. "It was so much fun, everything you could have dreamed of." More >

UP NEXT
Right-hander Felix Hernandez (5-3, 5.53 ERA) faces the A's for the third time this season in Thursday afternoon's series finale at 12:35 p.m. PT. Hernandez is 1-1 with two quality starts against Oakland, but he is in a stretch in which he's allowed three or more earned runs in five consecutive starts. Reliever Josh Lucas will make his first Major League start for the A's.