TOKYO -- Consider Josh Donaldson the A's everyday third baseman. Starting Thursday.

A's manager Bob Melvin opted to start Eric Sogard at third for Wednesday's regular-season opener against Seattle's Felix Hernandez and Co., but in no way did it reflect Donaldson's roster standing.

"I told Josh yesterday, 'You're our starting third baseman, you're just not starting tonight,'" Melvin said. "I wanted to get in not so much a left-handed bat, but a contact bat with Sogard. He's played well enough to deserve the start, but no matter what happens tonight, Donaldson will be in there tomorrow, and I still want him to think that he's the regular third baseman."

Melvin does not consider it a platoon situation. Rather, he's taking advantage of Sogard's presence during an adjustment period for Donaldson, who has had to endure plenty in the past month following his move from catcher to third base in the wake of Scott Sizemore's season-ending knee injury. Immediately plugging the right-handed hitter into a game against Hernandez wasn't a preferable scenario.

"He's playing a position that's a little out of character for him, he's shown he can play it, he's worked very hard -- I don't think anyone's worked as hard as he has this spring -- and I think, up to this point, he's done a great job," Melvin said.

Though four more exhibition games await the A's upon their return to the States this week, giving Melvin more time to determine who's best suited for the third-base job, it appears Sogard will remain a utility option because of his versatility around the infield.

"These are regular-season games, but we're still kind of in Spring Training mode, trying to find some things out and trying to find the right lineup and who fits where," Melvin said. "As of today, this is the lineup. I think it'll change against a left-hander tomorrow, and I'm not sure where it will be when we open back up at home again."

Cespedes ropes double in MLB debut

TOKYO -- Yoenis Cespedes appeared in a Major League starting lineup for the first time Wednesday, going 1-for-3 with a double in the A's 3-1 loss to the Mariners.

Cespedes struck out in his first Major League at-bat against Felix Hernandez in the second inning. His second time up, he ripped a ball to the warning track in center field and trotted into second base.

Cespedes did not appear in the middle of the order, as expected. A's catcher Kurt Suzuki found himself there instead.

Bob Melvin's first Opening Day lineup as A's manager featured Cespedes batting seventh and Suzuki, normally in that slot, up in the fifth hole as a reward of sorts.

"He deserves to be in there right now," Melvin said. "The way he's been swinging the bat, and also his numbers off of [Felix] Hernandez. With Yoenis, I think he's doing beautifully right now. I think it's more about Kurt than him."

It's hard not to consider Suzuki's history with Hernandez, against whom he's compiled a career .308 batting average (8-for-26) -- the best of any A's player. The 28-year-old backstop, making his fifth consecutive Opening Day start, is also hitting .300 in 12 exhibition games, the last two of which have included home runs.

Meanwhile, Cespedes is gradually making his way through an adjustment period against big league pitchers. The center fielder made his way through exhibition play with a .200 average, and his first assignment in a regular-season setting isn't exactly an easy one.

"I do expect Yoenis to be a middle-of-the-order bat at some point in time," Melvin said. "Whether that's tomorrow, a week from now, I'm not really sure yet. I think with all he's having to deal with right now, he's fine with where he is at this point in time tonight.

"I try to put myself in other people's shoes, and I can't even imagine what he's had to go through, and I think he's handled himself beautifully. He's already one of the guys, he's learning the language, and he's fitting in very nicely."

Cook seizes prominent role in A's bullpen

TOKYO -- Ryan Cook isn't the first name that comes to mind when thinking of the five-player deal that sent Trevor Cahill to Arizona, but it's one A's fans should get used to seeing in the later innings.

Cook, on his first career Opening Day roster, impressed manager Bob Melvin enough during the spring campaign -- opponents were just 2-for-23 against him -- to land a job as the primary right-handed setup option in the A's bullpen.

Things could change upon Joey Devine's return from the disabled list, but for now it's Cook and southpaw Brian Fuentes who will be looked upon for outs before closer Grant Balfour's arrival in the ninth.

"Those are the two guys I'm kind of targeting to have just before Grant," Melvin said. "You look at the personnel we have, and it really has to go on merit, based on what they've done in Spring Training."

The A's bullpen, which compiled a 3.74 ERA last year, is younger this season but well-balanced. In the two-game Opening Series in Tokyo, Melvin is equipped with three right-handers and three-left-handers, along with a length option in right-hander Graham Godfrey.

Worth noting

• The A's entered Wednesday having lost each of their last seven openers, marking the longest Opening Day losing streak in A's history. It is the longest active Opening Day losing streak in the Majors.

• The A's on Wednesday officially placed Joey Devine and Dallas Braden on the 15-day disabled list, retroactive to March 24. Braden continues his recovery from left shoulder surgery and is expected to be back in the rotation by May, while Devine is on the mend from right biceps tendinitis.