SEATTLE -- Aside from the expected hype, all was quiet on the Chris Carter front Monday night.

Around him, at least for one inning and three blink-of-an-eye outs, not so much.

During a time when all eyes were to be on Carter, the top prospect making his highly anticipated Major League debut, the A's not only found themselves on the wrong end of a triple play Monday but also on the losing end of a 3-1 contest to the Mariners at Safeco Field.

Carter, who admitted after the game he was "pretty nervous," endured an 0-for-3 night with two swinging strikeouts and a groundout while seeing just two balls come his way in left field. In the fourth, the 23-year-old rookie found himself in the on-deck circle watching Mark Ellis at the plate with no out and two runners on base, the A's down, 2-0.

Translation: The A's biggest callup of the year was facing a chance to show off his power -- he had 27 homers in Triple-A upon his promotion -- with runners in scoring position.

But Carter never saw an at-bat that inning. Instead, Ellis grounded into the A's second triple play of the year.

With Jack Cust at second and Kevin Kouzmanoff at first, Ellis pulled a sharp grounder to third base off Mariners starter Doug Fister, who watched Jose Lopez field the ball and touch the third-base bag simultaneously to force Cust for the first out. Lopez then threw the ball to second to force Kouzmanoff, and second baseman Chone Figgins completed the triple play to Casey Kotchman at first, although Ellis believed he beat the throw.

"I was safe," Ellis said. "There's not really much else to say."

"He was safe," A's manager Bob Geren said. "I didn't see it, but I was told he was safe. Obviously, it ended the inning. It was hit fairly decent. Another foot to the left, and it could have been a double."

Oakland's first triple play of the season came April 22 at home, where Alex Rodriguez began a 5-4-3 Yankees triple play courtesy of a Kurt Suzuki ground ball with Daric Barton and Ryan Sweeney on the bases.

"That's a very unique play," Geren said. "If you're going to turn one without a line drive involved, that's exactly the way you do it."

The play left Carter stranded on deck, and it also continued a trend the A's would prefer to see come to an end. The club is 0-for-35 with runners in scoring position since Friday -- numbers Geren wasn't too thrilled to hear.

"It's frustrating," he said, "in the respect that we had chances to score runs without a hit."

That was the story of the sixth inning, which began with Coco Crisp singling and scoring on an RBI double from Rajai Davis, marking the A's lone run of the night off Fister. Davis advanced to third on a groundout from Suzuki, but Cust and Kouzmanoff quickly garnered the final two outs without moving him home.

Fister, subsequently, left after six innings having given up just the one run along with seven hits, one walk and five strikeouts. His counterpart, meanwhile, went seven innings for the fourth time in his last six starts, but Vin Mazzaro was ultimately tagged with the loss despite his efforts.

The Oakland righty found himself in early trouble when he allowed back-to-back run-scoring hits to Lopez and Franklin Gutierrez in the first frame. He got through the next two innings unscathed, but in the fourth he allowed a leadoff walk to score on a sacrifice fly from Josh Wilson.

"That first inning was a little rough," Mazzaro said, "but after that, I was able to settle down, and I got into a groove. I made my pitches when I had to, just came up a little short."

Mazzaro surrendered three runs and five hits with two walks and five strikeouts en route to dropping to 6-4 on the season. The young right-hander is winless in his past three starts, but he didn't necessarily pitch all that poorly, his skipper insisted.

"He didn't get hit hard all night," Geren said. "If we get a couple hits with runners in scoring position, he'd have more room."

Carter, meanwhile, was simply satisfied to put a big league game under his belt despite tallying two swinging strikeouts in his first two at-bats.

"I was shaking," he said, "just trying to calm down. I was chasing those strikes, maybe a little over-anxious to hit something."

By night's end, though, he "felt fine out there," and Geren said the newcomer looked it, too.

"He hit the ball pretty hard that last time," the A's manager said. "He was locating his pitches well and just chased some balls.

"He doesn't seem to have that anxious look at all. He seems pretty relaxed."