Oakland A's fire Geren and appoint Melvin

NEW YORK (Reuters) - Bob Geren was fired as manager of the Oakland Athletics on Thursday and replaced by Bob Melvin.

Athletics' General Manager Billy Beane said in a statement that Melvin would serve as temporary manager for the rest of the season and the changeover was effective immediately.

"Bob Geren has been relieved of his duties as manager and former Major League manager Bob Melvin has been named interim manager for the remainder of the 2011 season," Beane said.

The Athletics are currently in the midst of a nine-game losing streak and sit at the bottom of the American League West standings with a 27-36 record.

Geren, 47, who had compiled a 334-376 record in his four completed seasons with the A's, was in the final year of his contract but facing increasing criticism over the team's poor performances and his managerial style.

Melvin, 49, posted a 493-508 record in seven previous seasons as a Major League manager. He led the Seattle Mariners from 2003-2004 and the Arizona Diamondbacks from 2005-2009.

The Athletics have won the World Series four times since they moved from Kansas to California in 1968. Their last championship was in 1989 and their last appearance in the World Series was 1990.

(Reporting by Gene Cherry in Raleigh; Editing by Julian Linden)