© 2014 MLB Advanced Media, L.P. All rights reserved.

2/21/2014 4:32 P.M. ET

Maurer misses workout with stiff back

PEORIA, Ariz. -- Right-handed pitcher Brandon Maurer was held out of Friday's workout after his back locked up on him in the morning, causing him to miss his first live batting practice.

Maurer, 23, said he didn't think the issue was serious and he hasn't had any prior problems, though it came at a bad time with pitchers just taking the mound to face hitters for the first time.

"I think I just must have slept on it wrong," Maurer said. "It's just a little stiff back, that's all. We'll see how it feels tomorrow and go from there."

Maurer is one of about 10 pitchers competing for starting rotation berths this spring in a wide-open camp. After Felix Hernandez and Hisashi Iwakuma, there are no locks for roster spots among the contenders.

Top rookie prospects Taijuan Walker and James Paxton both have a chance to win starting jobs, as do veteran non-roster invitees Scott Baker and Randy Wolf as they come back from Tommy John surgeries. Returners Erasmo Ramirez and Blake Beavan are also in the mix, along with Maurer and newcomers Matt Palmer and Mark Rogers.

Maurer was the surprise of last year's spring when he earned a rotation berth with a strong camp despite never having pitched above Double-A ball. He wound up going 5-8 with a 6.30 ERA in 22 games, including 14 starts.

McClendon plans to go with Ackley in left field

PEORIA, Ariz. -- Lloyd McClendon doesn't mince words once he has his mind set on something.

So while the new skipper is just getting to know his new personnel with the Mariners, he's not shy to share his thoughts once he's ready. When asked Friday whether Dustin Ackley was in the hunt for the center field job, McClendon replied:

"I doubt it. He'll probably be in left field the majority of time."

Why is he best suited for left field?

"Because that's where I want him," said McClendon.

The decision most likely has to do with Ackley's throwing arm, which isn't his strong suit. He did start 46 games in center last year after transitioning from second base at midseason. The feeling then was to put Ackley where he was most comfortable.

But with time now in Spring Training to work more on the outfield, his immediate future appears to be in left, where he started eight games in 2013.

McClendon likes Corey Hart in right field, assuming he can stay healthy coming off his pair of microfracture knee surgeries. He indicated Logan Morrison would get some work in left and right field later in camp, though he's currently spending time only at first base coming off some knee issues of his own.

As for center? The skipper noted that Michael Saunders, Abraham Almonte and Stefen Romero are capable of playing all three outfield positions, as can veterans Willie Bloomquist and Endy Chavez. Saunders and Almonte are the leading contenders there, though McClendon didn't list any pecking order.

He did mention young Xavier Avery, acquired last August from the Orioles in the Michael Morse trade, as another contender along with Romero, who offers a needed right-handed bat. Hart and Bloomquist are the only other right-handed hitters in that group, while Almonte is a switch-hitter.

When the team lined up for popup drills Friday, the outfield on the main field consisted of Ackley and Avery in left, Saunders and Almonte in center and Hart in right.

Felix, Walker start camp on slower schedule

PEORIA, Ariz. -- Pitching coach Rick Waits said Felix Hernandez and Taijuan Walker would continue on a slower schedule this spring than other Mariners hurlers, but expects both to be right on pace to open the regular season.

Hernandez, 27, will follow the exact same schedule he's used in recent Spring Trainings, as the Mariners try to lighten the early load on a pitcher who has thrown 232 or more innings in each of the last four seasons.

While most Mariners pitchers have already thrown three bullpen sessions and now a live batting practice outing, Hernandez still has to throw his third bullpen and then will have one live BP outing and a simulated game on one of the practice fields before he makes his Cactus League debut in early March.

"He won't be in the first games, same as he's done every year," Waits said. "He gets his stuff going on a backfield, then he's ready. He threw 22 [Cactus League] innings last year and 17 the year before. So somewhere between 20-25 innings is what we'll shoot for."

Waits said he has no concern over Hernandez getting ready in time by Opening Day.

"I don't because he's in great shape this year," said Waits. "He threw plenty enough before he came. And his first bullpen, he seemed ahead to me from his first bullpen last year."

Walker, 21, is a slightly different situation. The youngster had a sore arm upon arrival after throwing some hard sessions getting ready for camp. So he was held back initially and is just now gearing up.

Walker had a strong second bullpen session Thursday, but will still need several more bullpens before he graduates to live batting practice. Waits said Walker is completely healthy now, just slightly behind the other pitchers due to his late start.

"There are no issues at all," said Waits. "Today was an important day, the day after he threw his second bullpen, and he said he felt great. Hopefully he doesn't have any setbacks. We've got enough time to get him ready, but he's a little behind Felix."

Walker threw 35 pitches in Thursday's bullpen session, up from the 25 fastballs he fired in his first mound appearance Monday.

"I was pleased," said Waits. "He threw a few curveballs, but mostly fastballs and changeups. We need to do that again. There's no hurry to get to the off-speed pitches. The idea is to get the arm strength built up. When you've got the arm strength, you can throw anything."

Worth noting

• Fourteen pitchers threw their first live batting practices on Friday, including Scott Baker, Randy Wolf and Zach Miner, a trio of veteran non-roster invitees who are coming back from Tommy John surgeries in 2012.

"I thought the ball came out good for all three of them," said McClendon. "They're obviously a little rusty, but that's OK. They came through it good and it looked free and easy. That's what I was looking for. We're not looking for any kind of results, just free and easy."

• Two veteran relievers -- Fernando Rodney and Ramon Ramirez -- threw bullpen sessions instead of live BP. Rodney was just getting extra work before making his live debut, while Ramirez was a late arrival to camp due to visa problems getting out of the Dominican Republic.

• While most hitters continue taking limited swings in the early days of live BP, Michael Saunders ended his outing against Charlie Furbush with a blast over the right-field fence. Saunders and Furbush both threw their arms in the air as the ball cleared the wall, Saunders in jubilation and Furbush in mock indignation.

"Somebody had to give up the first one," Furbush said.

• Early observation on McClendon's first Mariners camp: Coaches work at a quick pace when doing drills with their position groups. And once everything is accomplished, they move on, even if ahead of the timed schedule.

"Having been a player, I know that when you start getting monotonous with drills, nobody pays attention," McClendon said. "My thought process is, let's have a camp that is precise, quick and to the point. Guys get it, they retain it and we move on. It keeps camp interesting and happy for guys. You want to have a good, upbeat, happy type of camp."

Greg Johns is a reporter for MLB.com. Follow him on Twitter @GregJohnsMLB as well as his Mariners Musings blog. This story was not subject to the approval of Major League Baseball or its clubs.