OAKLAND, Calif. — Felix Hernandez can take some comfort in knowing his next mound appearance just might find him surrounded by the kind of talent too often lacking in Sunday's series finale here.

Hernandez heads to the All-Star Game this week as the lone representative of a last-place Mariners team beaten 2-1 in 13 innings by the Oakland Athletics on a seemingly interminable day in which both teams struggled to generate offense.

The Mariners closed out the pre-All-Star break portion of their schedule 15 games under .500 and with several young hitters potentially headed to Class AAA.

"Those guys, they're trying very hard," Hernandez said after taking a no-decision with 7-2/3 innings of one-run ball. "They want to score runs. I believe in this team. I believe in these guys. We're going to be better. This cannot happen all of the time, so we're going to be better."

The trouble is, what happened in front of 20,075 fans at the Coliseum has taken place too often for the team's liking. Mariners manager Eric Wedge hinted all weekend that changes are coming and — despite some individual surges — the overall picture hasn't changed much since the team arrived here Friday.

The game ended with hundreds of seagulls flying over the field and making it difficult for outfielders from both teams to catch fly balls. Michael Saunders notched a double in the 13th on a routine fly to right that was lost by Oakland's Seth Smith, but got no further.

Then, Jemile Weeks led off the bottom of the frame with a single against Oliver Perez. Josh Reddick followed with a double to the gap in left-center to easily score Weeks for Oakland's second walkoff win this series.

"I felt like we had some good at-bats early on," Wedge said. "We had some hard outs, hit some balls on the nose right to them. But later, it got worse.

"When you're in that type of ballgame, you have to do everything you can to put anything together, put runners in scoring position ... and you have to come through. We didn't do it."

Hernandez threw 114 pitches and said it will be "pretty tough" to pitch in Tuesday's All-Star clash. But he also said he'll be ready if needed.

He fought to keep his team close while mound counterpart Bartolo Colon was retiring 17 batters in a row at one point. The Mariners finally tied it 1-1 off Colon with two out in the sixth when Dustin Ackley notched his second single of the game, took third on a bloop hit to left by Ichiro and scored on a single to right by Saunders.

Hernandez had some early help from the gloves behind him, with shortstop Brendan Ryan saving a run by diving to snag a grounder far to his right and keep it from getting into left field in the first inning. Justin Smoak then speared a hard grounder behind his first-base bag with a runner on third to prevent another run in the second inning.

But the Mariners once again could not get anything going at the plate. They came into the game donning the old Seattle Rainiers uniforms as part of a 1955 Turn Back the Clock Day at the ballpark.

And for a handful of young Mariners, the next uniform they put on in a game could belong to the Rainiers as well — the AAA Tacoma version. Ackley had trotted out for pregame warm-ups on Sunday saying he'd like to finish with a strong performance and did just that.

He is one of the young hitters who could be AAA-bound, in addition to Smoak and Jesus Montero, who've all spent the past several weeks struggling to hit.

"I'm real close," Ackley said before the game. "I feel like I know a lot of things I need to be doing, but you've got to take them into the game."

Wedge has said as much, indicating that his players have enjoyed solid batting practice sessions.

"I've gotten into a lot of bad habits with game swings and it's something I need to get out of," Ackley said, adding that his overall approach remains the same.

Ackley now plans to "relax and get some good, much needed rest" during the break.

Smoak is planning much of the same. He doubled with two out in the ninth on Sunday to force Colon from the game. Smoak also just missed a fifth-inning home run on a ball that hooked foul.

"You always think about it," Smoak said of first-half struggles. "You wonder whether it's going to get better. I hope so. I've felt like I haven't done well at all."

The question now is whether either will get another chance without a AAA stopover.

Same for Montero, who didn't play in this series after suffering a mild concussion in the homestand finale last Wednesday. He is batting .245 with an on-base-plus-slugging percentage (OPS) of .657.

Smoak's numbers are worse, with his batting average at .203 and an OPS of .597. Ackley is hitting .233 with a .636 OPS.

"Whatever we decide to do, if anything, we want to make sure we're doing it for the right reasons and not just being emotional with it," Wedge said. "I think we do a pretty good job with that."

Geoff Baker: 206-464-8286 or gbaker@seattletimes.com. On Twitter @gbakermariners.