The Philadelphia Phillies sacked manager Joe Girardi on Friday, citing the team's sluggish start to the season.
Phillies president of baseball operations Dave Dombrowski said in a statement the team had decided to part company with Girardi after a "frustrating" campaign.
The Phillies are rapidly losing ground on the in-form New York Mets in the National League East, 12 games adrift of the leaders with a 22-29 record.
"It has been a frustrating season for us up until this point, as we feel that our club has not played up to its capabilities," Dombrowski said in a statement.
"While all of us share the responsibility for the shortcomings, I felt that a change was needed and that a new voice in the clubhouse would give us the best chance to turn things around."
The Phillies have dropped seven of their last nine games and are in third place in the division.
Dombrowski said bench coach Rob Thomson would take over the managerial duties from Girardi for the remainder of the season.
"I believe we have a talented group that can get back on track and I am confident that Rob, with his experience and familiarity with our club, is the right man to lead us going forward," Dombrowski said.
The 57-year-old Girardi has been Phillies skipper for the past three seasons but failed to take the team to the playoffs. Philadelphia has not reached the postseason since the 2011 campaign.