NEW YORK — Andrew Bailey was driving along, talking to his agent on a handsfree cell phone, when another call came in.

Figuring it was probably his mom, the Oakland Athletics closer finished one conversation and clicked over.

Good news, kid: You’re the Rookie of the Year in the American League.

“At first I thought it was a prank call. Which one of my friends is playing a prank on me?” Bailey said. “I didn’t want to take my eyes off the road.”

Nope, this was legit. Bailey became the latest A’s player to take home the rookie prize, and Florida Marlins left fielder Chris Coghlan won the NL honor in a close vote Monday.

Coghlan edged Philadelphia pitcher J.A. Happ, receiving 17 first-place votes and 105 points in balloting by the Baseball Writers’ Association of America. Happ, the only player picked on all 32 ballots, had 10 first-place votes and 94 points.

“It’s very exciting,” Coghlan said during a conference call. “I couldn’t have written it better.”

Bailey, a surprise All-Star this season who had 26 saves and a 1.84 ERA, was selected first on 13 of 28 ballots and finished with 88 points. Texas shortstop Elvis Andrus was the runner-up with 65 points, one more than Detroit pitcher Rick Porcello.

Both award winners enjoyed fast success in new roles.

After struggling as a starter in Double-A last year, Bailey switched to the bullpen and became a major league All-Star in July. Coghlan, a second baseman in the minors, made a hasty shift to left field in May and found a home atop Florida’s lineup.

“It wasn’t the easiest transition,” Coghlan said. “I just tried to work as hard as I could to get as comfortable as I could in the outfield.”

The 24-year-old Coghlan overcame an early slump. He batted .321 with nine homers and 31 doubles in 128 games. He scored 84 runs and drove in 47.

Called up from the minors in May, Coghlan topped NL rookies in batting average, runs, hits (162), total bases (232) and on-base percentage (.390). He became the third Florida player to win the award, joining Hanley Ramirez (2006) and Dontrelle Willis (2003).

Coghlan played one minor league game in left — without getting a fly ball. He finished the season with five errors.

After winning Monday, Coghlan thought of his father, who died when he was 15.

“That was a tough point in my life,” Coghlan said. “He was the one who instilled the work ethic in me and taught me the game. I know that he’s proud, and I’m proud to win this award and he’s definitely a big part of it.”

Atlanta pitcher Tommy Hanson finished third in a competitive field with two first-place votes and 37 points. Pittsburgh outfielder Andrew McCutchen, who came in fourth, also was chosen first on a pair of ballots.

Bailey went 6-3 and had 24 more saves than any other AL rookie. The 25-year-old right-hander also led the league’s rookies in ERA while striking out 91 and walking 24 in 83 1-3 innings. He yielded only 47 hits, holding opponents to a .167 batting average.

He is the eighth A’s player to win the award, tying the New York Yankees for most in the AL.

“I had never been a reliever in my life, so the opportunity to just go in for an inning and let loose was something I had never experienced before,” Bailey said. “Just took the opportunity and ran with it.”

Bailey made the Oakland roster and soon got a chance to close partly due to injuries. He took advantage of it, earning a trip to the All-Star game.

Bailey became the third A’s player in six years to win the rookie award, joining closer Huston Street (2005) and shortstop Bobby Crosby (2004).

“Certainly the first credit goes to Andrew. It’s also a credit to our staff and the people who saw the change to the bullpen being a good step,” general manager Billy Beane said. “He had always been a prospect, but as a starter he hit a wall. There was a suggestion to move him to the bullpen and he hasn’t looked back. Since he made the switch to the ’pen he’s been dominant.”