PHOENIX -- One year ago to the day, Jarrod Parker and Tommy Milone essentially were keeping their own counsel, hoping for the opportunity to fulfill childhood dreams.

Rookies, they understood, are best seen and rarely heard. That made for a relatively quiet clubhouse in Oakland, where 19 rookies -- 12 of them pitchers -- were summoned by manager Bob Melvin along a magical ride to a 2012 American League West title. The 25-man postseason roster included 12 freshmen.

"You didn't hear this music in here last spring," Josh Reddick, Oakland's slugging, Gold Glove Award-winning right fielder, was saying on Thursday morning in a vibrant A's clubhouse. "We were all new -- new faces in a new place. We know each other now. We're a lot more comfortable."

A season of unimagined success stories, from rookie pillars on the mound to emerging stars on the field, will do that.

Parker and Milone were the most consistently productive members of an A's rotation that was the foundation of the club's ascent, along with the power production of a deep lineup featuring Cuban import Yoenis Cespedes and Reddick.

"We definitely have the ability to bang it," said Milone, a lefty with superb command from Saugus, Calif., and the University of Southern California. "That's where we're most underestimated.

"We started slow but knew what we had. Once we started going, we didn't stop."

It took Justin Verlander and the Tigers to end the ride in an AL Division Series that went the distance.

Milone and Parker, a resourceful right-hander from Indiana, each won 13 games, leading the staff and sharing a franchise record for rookies. It was the first time since Joe Black and Billy Loes of the 1952 Brooklyn Dodgers that a pair of rookies on the same staff claimed 13 or more victories.

Down the stretch, with Bartolo Colon suspended, Brandon McCarthy injured and Brett Anderson limited to six starts in his recovery from Tommy John surgery, an all-rookie rotation of Milone, Parker, A.J. Griffin, Dan Straily and Travis Blackley captured 20 of 25 decisions. A's rookies won an MLB-record 54 games.

"They found some sort of identity last year pitching in big ballgames," said Melvin, who won the AL Manager of the Year Award. "They didn't pitch like rookies. We kind of look at them as veterans.

"They basically all pitched a year together, had success, pitched well in the postseason. I think they have a chance to push each other. They kind of had a competition [among themselves] that played out. That dynamic could be better."

Parker, 24, and Milone, who turned 26 last week, watched the collective confidence level soar in the youthful rotation as the season played out. Both had come to Oakland in winter deals -- Parker from the D-backs, Milone from the Nationals. Oakland general manager Billy Beane detached proven goods for promising talent and hit the jackpot.

"The game starts with the starting staff," Parker said. "In a successful one, you become friends and are competitors as well. We have a chance to one-up each other every time out.

"It's only our second spring together, so relationships [are] something that's developing. We're all pretty much low key. Bartolo is the elder statesman, and he's quiet as can be. He's a professional; everybody on our staff is that way."

The A's have depth everywhere with some winter improvements by Beane, who has an abundance of potential starting pitchers.

After leading the staff with 190 innings and 31 starts and going 13-10 with a 3.74 ERA in 2012, Milone came to camp with the same attitude he brought last year.

"I have to go perform to win a spot," Milone said. "That fire that drives you to win a spot, you want to keep that mentality and pitch the way you can pitch. What we had last year was a fun competition, trying to outperform the next guy."

Parker, who didn't debut until April 25 after opening the season at Triple-A Sacramento, delivered 181 1/3 innings in 29 starts. He was 13-8 with a 3.47 ERA.

Fellow rookies Blackley (6-4, 3.86), Griffin (7-1, 3.06) and Straily (2-1, 3.89) all came up big when it counted.

"We have seven, eight guys who can start," Parker said. "There's a lot of competition, and that's something we like. We definitely think we're guys who should be out there. The confidence is there."

With 10 different starters going to the post, the A's had the ninth-best ERA in the Majors among all rotations at 3.80. The bullpen was even better at 2.94, which ranked fourth in the game and second in the AL.

"It's pretty impressive, kind of a reward for the work we put in," Parker said. "We kept grinding it out during some tough days when it could have gone the opposite way."

On June 30, having dropped their third game in a row in Texas, the A's were 37-42 and 13 games off the Rangers' division pace. But Blackley outdueled Yu Darvish, 3-1, the next day to prevent a four-game sweep, and when the A's returned home, Parker shut down the Red Sox to kick off a three-game sweep.

From July 1 to the finish, Oakland went 57-26, overhauling Texas by winning the final six games and eight of the last nine.

"We got hot at the right time and went into the last week putting ourselves in a position to win [the division]," Parker said. "To look at the year as a whole, what's impressive is the team effort. So many guys contributed."

Parker and Milone realize this could be the start of something big. They also know those competitive fires that ignited an Oakland inferno must continue to burn bright.

"What happened last year was definitely gratifying," Parker said. "We have to hold onto that mental attitude and routine and keep this going."