OAKLAND -- The Mariners looked to be in good shape as they headed to extra innings on Saturday evening. With the heart of the order set to bat in the top of the 10th inning, Seattle had a good shot at securing a series win and getting in position to sweep the A’s.

Instead, after a mixture of bad luck and defensive miscues, the Mariners will need to prove their mettle in Sunday's rubber match after dropping a 4-3 decision to Oakland in 10 innings.

After recording double-digit run totals in back-to-back games, the Mariners' production took a dip on Saturday, as they were held to three runs on seven hits.

"Offensively, it was a little bit of a struggle today," manager Scott Servais said. "We need to do more than that. … You need a little luck in those extra-innings games. You need some things to go your way, and that certainly didn't happen."

That absence of luck was evident on Saturday, as right-hander Logan Gilbert allowed three runs (two earned) over five innings to keep his team in the game. Seattle’s lineup, though, struggled to scratch anything across, going 1-for-7 with runners in scoring position -- until Eugenio Suárez came through with a two-out RBI knock in the top of the eighth inning, which tied the game and ultimately sent it to extras.

With Ty France on second as the automatic runner and Jesse Winker, Mitch Haniger and J.P. Crawford set to hit, the top of the 10th inning looked like one of the Mariners' best chances all game. But things quickly did not go their way.

Winker started things off by lining out on the first pitch he saw from A's closer Dany Jiménez. He hit the ball right at first baseman Seth Brown, which didn't give France an opening to advance.

Haniger, too, swung at Jiménez's first offering. This time, France took off on contact -- but Haniger grounded the ball to A's shortstop Nick Allen, who made a heads-up play to throw France out at third.

Crawford may have been the least lucky of all, as he hit a sharp liner straight into the glove of A's second baseman Jonah Bride. Crawford's drive had an 82 percent hit probability, but it just ended up in the wrong place.

"It's 105 [mph] off the bat. The guy's standing right there," Servais said. "What are you going to do? It's baseball -- I know people hate that. But if you've been around it enough, you need some things to go your way, and they made plays today."

That bad luck continued into the bottom of the 10th. With the bases loaded and five men in the infield, Oakland DH Sheldon Neuse hit a chopper that reliever Diego Castillo could not field cleanly, allowing the A's to walk it off.

"We got the ground ball," Servais said. "It just kind of went in a funky place. … I just felt confident [Castillo] was going to get them to hit the ball on the ground. They just hit the perfect grounder, and that was the ballgame."

That wasn't the only defensive bobble for the Mariners on Saturday -- they gave up a three-spot to the A's in the fifth inning, due in part to a fielding error and some difficulty with the notoriously tough Coliseum outfield sun.

"It's not something to worry about," Gilbert said. "That's baseball, it happens. The sun out there, whatever -- nothing to worry about. Those guys are really good behind me."

It was a somewhat uncharacteristic defensive showing, as entering Saturday the Mariners' .990 fielding percentage was tied with the Cardinals for best in the Majors, and their cumulative nine Outs Above Average ranked eighth in the league. But Seattle slipped up, and Oakland was able to capitalize.

"We did give up some free bases today," Servais said. "I don't care who you're playing. You can't give up the free bases, and they took advantage of it."