PHOENIX — There is no doubt that Brett Anderson is a stand-up guy who wants to be the leader of the A's rotation.

What is less clear is whether or not the A's need him to fill the role of a classic leader the way Dave Stewart did it in Oakland a generation ago.

Stewart was outgoing, bold, an oversized personality at the top of a pitching staff that needed that. Bob Welch, Mike Moore, Storm Davis, Ron Darling, Curt Young and the like were good pitchers, but Stewart ground out 20-win seasons and ground up American League hitters in the process.

More than once, with the A's backs against the wall, Stewart huddled with his teammates before big games and "guaranteed" a win. And he produced.

By his own admission, Anderson doesn't have that kind of personality. He's perfectly willing to talk and engage the media, but he's not ready to do stand-up routines. If what the A's need is someone to rally the troops with his vocal cords, he's not the right fit.

But heading into the 2013 season, the A's need someone at the top of the totem pole, the kind of leader who leads by example on the field, and by that definition, Anderson is a good fit.

"I think every teams needs a pitcher where they can say, &‘we feel this is our ace,'" Young, now the team's pitching coach, said. "And Brett has put himself in that position. There are different kinds of leaders.

"Brett wants to be seen as one of the best pitchers in Major League Baseball. As he does that, he'll lead by example."

Anderson came back from shoulder surgery last year and won his first four decisions. Then, after one loss, he was taken out in the third inning of a game in Detroit with a right oblique injury. Other pitchers might have called it a season, but Anderson fought to come back and managed to start and win Game 3 of the playoffs, throwing six shutout innings while holding the vicious Tigers lineup to two hits.

"It was important to me to get out there, to help the team," Anderson said. "I felt the oblique just a little in that game, but I was able to rest it after that and haven't felt it since."

As for the leadership role, Anderson, ever the team player, sees a role that needs to be filled.

"It's a little weird; I'm 25 and I have some of the longest tenure on the club," he said. "I don't know how that happened. I don't classify myself as old. But I have to be more of a leader. I'm not a rah-rah, vocal guy, but guys can come ask questions. And maybe some of the eccentric personality will come out now."

Bob Melvin has never had the leader of a pitching staff in any of his three stops as a manager — Seattle, then Arizona before Oakland — be so young. "Maybe Brandon Webb in Arizona, but he was 26, 27," Melvin said.

"We needed a leader last year, and we had (Brandon) McCarthy," Melvin said of McCarthy, who now is with the Diamondbacks. "We don't need one so much this year. We had Jarrod Parker start Game 1 of the playoffs last year, which is huge for a pitcher in his first big league season. And he pitched great. Our kids, all of them, did a lot of growing up last year.

"(Anderson) isn't going to be a great vocal guy in the clubhouse, but he's already proven that he's going to be a stand-up guy anytime you give him the ball. And that's what we need. He's not a leader like Roger Clemens was or like Dave Stewart was. But his stuff leads anybody."

Anderson is a left-hander blessed with a mid-90s fastball and two breaking balls, and when he throws, hitters generally swing early.

The delivery of his fastball and his breaking pitches are so similar that batters have to respect the fastball and swing assuming the fastball is coming.

When the curve shows up — and he can throw the curve in any count — the hitter can look foolish chasing slow stuff.

"You always know Brett's not going to be the vocal guy," Melvin said. "But he can pitch."

And that, at its base, is the essence of leading.

Lefty reliever Hideki Okajima signed his minor league contract and took part in a full workout Tuesday, although he didn't throw off a mound. One reason he liked Oakland is that he worked under pitching coach Curt Young in the 2011 season in Boston. "I think getting him is a very big deal," Young said.

Melvin said he likes the effort turned in by right-hander Andrew Carignan, throwing 60 feet on the side, 25 pitches in all, just seven months after Tommy John-style ligament replacement surgery in his elbow. He could possibly pitch during the second half of the season.

Second baseman Grant Green and third baseman Josh Donaldson both made their first appearances in the A's camp and took part in workouts.

Right-hander Fernando Rodriguez, a right-hander who came to Oakland along with Jed Lowrie from Houston, caught Melvin's eye. "He's a right-hander with a big arm and nice downward plane to his pitches," the manager said. "The ball doesn't spend too much time in the strike zone."

Lefty reliever Pedro Figuer-oa has pulled an about-face and will not be pitching for the Dominican Republic in the World Baseball Classic. That's good news for the A's, who won't give up anyone on their roster to the WBC.

Also catching Melvin's eye was Arnold Leon, a right-hander out of Mexico. The 24-year-old pitched this winter in his native Mexico and reported in great shape.