SURPRISE, Ariz. -- Making his third start of the spring Saturday in competition for a back-end rotation spot, A's right-hander Dan Straily mixed in his slider more against the Rangers, turning in what he called his best outing so far.

The 24-year-old began his day by striking out the side in the first inning, inducing swinging strike threes on sliders from Texas All-Stars Ian Kinsler, Lance Berkman and Adrian Beltre.

"It was fun to see it is still sharp and working for me," Straily said. "It was good to get out there, throw it and see some late movement on it. I was able to get ahead and try to get them sped up with the fastball then slow them down with the slider. It was good."

Straily previously used the pitch sparingly this spring, because he was still trying to build up his arm.

"I didn't want to rush on it, it's not a pitch that I try to throw too often," he said. "I don't want to find myself on the DL because I tried to throw too hard."

The right-hander allowed two runs in the second inning, but only one came earned after Yoenis Cespedes misplayed a ball in left field. Straily settled back down in his final inning of work, retiring the side in order on just five pitches. He credited the quick inning to his offense, which sent up seven batters to the plate in the previous inning to give the pitcher some rest.

"I definitely came out and thought I was throwing a little bit slower, but it was the most effective inning I've had this spring," Straily said. "The long inning gave me the chance to catch my breath. The last thing you want to do is throw 30 pitches, wait for eight pitches, then go right back out there."

On the day, Straily surrendered two runs (one earned) on three hits and a walk while striking out three batters over three innings. After he exited the game, Straily tossed another 15 pitches in the bullpen to stretch him out even further.

"He mixed his pitches well, got himself into trouble a couple times, but I thought his stuff was good," A's manager Bob Melvin said. "Last year, if he got off to a bad start, it was tough for him to recover. He definitely has the stuff to recover, though. It's just maturity for him."

In his previous two spring appearances, the A's No. 2 prospect as ranked by MLB.com gave up four runs in 3 2/3 combined innings.

Billings' versatility a big draw for A's

PHOENIX -- With less than a month until Opening Day remaining, the A's reassigned Bruce Billings to their Minor League camp Saturday, meaning he'll start the 2013 season at Triple-A Sacramento. But even without a 25-man roster spot with his name on it, Oakland still sees the right-hander as a valuable piece to their club moving forward because of his versatility and experience.

"He's depth for us. ... He's a guy who needs to stay ready over the course of the season because he can make an impact at any particular time," A's manager Bob Melvin said. "He can pitch at the big league level -- he's just probably got a few guys ahead of him at this point. But he does have good stuff and he's versatile. We can start him or bring him out of the 'pen."

Billings made a few appearances with Oakland in 2012, but he spent the majority of the year in Sacramento, posting a 3.98 ERA in 133 1/3 innings as a starter. So far this spring, the 27-year-old has performed well, allowing one earned run over 4 2/3 innings.

"I'm just trying to get ready to play baseball and make whatever impression I can on the team," Billings said. "I want to be a positive influence in the clubhouse and be myself."

Even though the right-hander has gotten good results this spring, he is still tinkering with a few of his pitches while he can before he settles in later in March for final preparations for the year.

"I'm always messing with grips, always experiment with how you want to use pitches in certain situations," Billings said. "We're just getting ready for the regular season, so everything is just practice now. I didn't have my fastball command in my first couple outings; I was just kind of getting by with my stuff. But now we're kind of getting into the thick of camp, and I'm starting to feel more comfortable."

A's optimistic about Balfour, target Monday for Weeks

PHOENIX -- A's closer Grant Balfour threw his fourth bullpen session Saturday since undergoing knee surgery last month while second baseman Jemile Weeks' return to game action could be pushed back to Monday, according to Oakland manager Bob Melvin.

The A's hope Balfour, who saved 24 games for the club last season, will make at least five appearances this spring before heading back to California for Opening Day.

"He's on a good schedule right now," Melvin said. "If he continues at the pace he's on right now and there are no setbacks, he certainly would be ready for the season."

Melvin added he's not sure yet what the next step for Balfour is moving forward, but he would likely need to throw in a simulated game and/or batting practice before making his spring debut.

Meanwhile Weeks, who is recovering from a bruised right shoulder he injured on March 1, participated in all team drills Saturday, but his manager might give him an extra day of rest before reinserting him back into the lineup. Melvin originally said Friday the team targeted Sunday for his return.

"If you're in spring and you get to the point where it's time to play, maybe it's prudent to give him one more day." Melvin said. "We'll see tomorrow, if he's close to 100 percent tomorrow, there's a chance he plays, but if not, maybe we give him one more day."

Weeks was 6-for-11 with five RBI in four spring training games before he suffered the injury.

Worth noting

• In addition to Bruce Billings, the A's also reassigned Sonny Gray and Justin Thomas on Saturday.

• Addison Russell, Oakland's No. 1 prospect according to MLB.com, got his second start of the spring on Saturday, batting ninth and in the designated-hitter spot.

"When you bring a kid like that into camp, one of the top prospects, he's here for a reason," A's manager Bob Melvin said. "I want to get him some at-bats. I think for a youngster, sometimes the DH role can take away some of the nerves and get him more comfortable. He's done a nice job, though. He doesn't look like he's 19 years old. He doesn't act like it, either. It's always nice to reward somebody like that."

In his first 12 at-bats of the spring, Russell has four hits and a pair of RBIs.

• Melvin said Tommy Milone is using part of this spring to learn how to pitch differently in smaller parks while away from Oakland. The 26-year-old finished with a 2.74 ERA at the Oakland Coliseum last season but struggled on the road with a 4.83 ERA.

"You can't help but look at the numbers, because of the way his style of pitching plays at bigger ballparks like ours," Melvin said. "He throws a lot of strikes, and maybe at times you go a little bit out of the zone more in some smaller parks, where balls in the air end up getting out of the park. I know he's working to get more ground balls, too."

• Seth Smith and Josh Reddick spent time Saturday taking grounders at first base during workouts.