ANAHEIM -- An already thin Mariners roster took another hit Monday when outfielder Jason Bay was held out of the series opener against the Angels with a sore hamstring muscle.

Bay normally would have been in the lineup against the left-handed Jason Vargas, but Raul Ibanez instead got the call after the 34-year-old Bay felt his hamstring tighten up during Sunday's game in Oakland.

"He got a little knot in there," manager Eric Wedge said. "We got him out here early and tried to have him run a little bit, but we talked about it and felt we'd be putting him in harm's way."

Wedge is already operating with Michael Morse playing first base while still hampered by a sore right quadriceps and Kendrys Morales limited strictly to designated hitter duties by a sore back.

Justin Smoak is eligible to return from the 15-day disabled list as he continues a Minor League rehab stint with Triple-A Tacoma due to a strained oblique, but the first baseman went 0-for-4 on Sunday and is hitting .188 (3-for-16) in four games with the Rainiers.

General manager Jack Zduriencik is with the Rainiers in Sacramento and planned to watch Smoak play again Monday night before the club talked further about whether he's ready to return.

Zunino handling transition to Majors with ease

SEA@OAK: Zunino's first career homer puts Mariners up

ANAHEIM -- Mike Zunino has proven to be a quick learner in his first few Major League Baseball games and the Mariners' rookie catcher says he's welcomed help from all angles since getting called up six days ago from Triple-A Tacoma.

His most direct help the last few days has come from new teammate Henry Blanco, the veteran catcher signed Friday when Kelly Shoppach was designated for assignment. Blanco's primary role is to help mentor Zunino, who is 19 years younger at age 22.

"It's been awesome," Zunino said before Monday's series opener with the Angels. "He's a guy with a lot of knowledge and I'm just looking forward every day to being around him and just picking his brain for as much as I can.

"He looks no part of 41, the way he catches and the way he plays. It's one of those things where I'd love to be playing like he is at that age. It's awesome. It really is."

Zunino said he's leaned on teammates like Raul Ibanez and Kyle Seager for off-field details on what to wear and how to handle himself in certain situations and he's been pleasantly surprised by the information provided in scouting reports from the club's advance scouts prior to each game.

"They're more in-depth and everything is just kind of handed to you," he said. "All you have to do is watch a little film and sort of get a feel on them and everything else is sort of laid out on paper for you."

That said, Zunino's quick success is a tribute to his own preparation and skills. He works out early every day in the cage, taking extra swings and then does stretching and conditioning work. Once or twice a week in the Minors, he spent time with a pitching machine doing defensive fundamental drills and he intends to renew that routine once he gets settled in with the Mariners.

"I try to keep everything as fine-tuned as possible," he said.

"He pays attention well," manager Eric Wedge said. "He's always talking to somebody. He's a good listener, asking good questions. He's a student of the game."

It's all added up to a nice start as Zunino hit .300 in his first three games with a home run and has handled himself impeccably behind the plate. And day by day, his comfort level is increasing.

"Yeah, it's one of those things where everything has gone smoothly so far," Zunino said. "So I'm just looking to hopefully continuing in the right direction."

Mariners sign two more Draft picks

2013 Draft: MLB.com looks at the Mariners' picks

ANAHEIM -- Fourth-round Draft choice Ryan Horstman and 11th-rounder Zack Littell both signed contracts with the Mariners on Monday as the club now has inked 10 of its top 12 picks.

Horstman, a 6-foot-1 left-hander out of St. John's University, will report to short season Class A Everett. Littell, a 6-foot-3 right-hander out of Eastern Alamance High School in Mebane, N.C., is headed for the Arizona Rookie League team in Peoria.

Second-round pick Austin Wilson, an outfielder out of Stanford, and shortstop Tyler Smith from Oregon State (8th round) are the only picks in the first 12 rounds that have yet to sign. The club has inked 15 of its 40 selections overall.

Several of the Mariners top collegiate picks, including first-rounder DJ Peterson out of New Mexico, are slated to play for the Everett team that opened play with a three-game sweep in Spokane over the weekend. Peterson hasn't played yet, but is expected to be with the Aqua Sox as they open their home schedule Monday night in Everett.

Worth noting

• Dustin Ackley went 0-for-4 in Tacoma's 6-3 loss at Sacramento on Sunday, snapping a 16-game hitting streak in which he batted .435 with 12 runs, five doubles, two home runs, 11 RBIs and 15 walks. Ackley continues playing center field for the Rainiers and has hit .390 with a .495 on-base percentage in 18 games since being sent down.

"The transition has been good," manager Eric Wedge said. "He's getting reps in left and center. By all accounts, the transition has been good and he feels comfortable out there."

• Franklin Gutierrez didn't play Sunday due to a planned day off for Tacoma as he continues making slow progress in his second rehab stint with the Rainiers. Gutierrez is eligible to come off the 60-day DL on June 22.