BALTIMORE -- Since the final days of last season, speculation swirled over Fredi Gonzalez's security as Marlins manager.

In a unexpected move on Wednesday morning, the Marlins announced that Gonzalez had been dismissed, as well as bench coach Carlos Tosca and hitting coach Jim Presley.

The team named Edwin Rodriguez interim manager, promoting him from Triple-A New Orleans. Brandon Hyde was named to take over as interim bench coach, and John Mallee was made interim hitting coach.

Hyde was the organization's Minor League infield coordinator, and Mallee served as the organization's hitting coordinator.

"It is never easy to make a change in managers," Marlins owner Jeffrey Loria said in a statement. "Fredi has been with our club for four years. We have become close, and I am extremely fond of Fredi. I, along with all our fans, am grateful for Fredi's contributions. At the same time, we can't let personal feelings get in the way of taking steps that we believe are necessary to improve our ballclub."

Marlins president David Samson, president of baseball operations Larry Beinfest and general manager Mike Hill are scheduled to meet with the media at 4 p.m. ET at Camden Yards, where the team is playing a three-game series against the Orioles.

Gonzalez, scheduled to depart Baltimore on Wednesday afternoon, is expected to speak to the media during a conference call on Thursday. He told reporters that he was informed of the team's decision at about 7:30 a.m. ET.

Entering the season with playoff aspirations, the Marlins improved to 34-36 after beating the Orioles, 10-4, on Tuesday night at Camden Yards.

It's been a rough first half for the Marlins, who are 7 1/2 games behind the Braves in the NL East and six games out in the Wild Card standings.

The early part of the season included a run-in with All-Star shortstop Hanley Ramirez. Ramirez was benched for not hustling on the field after the second inning of a game against Arizona on May 17.

After that game, Gonzalez said: "We expect an effort from 25 guys on this team; when that doesn't happen, we've got to do something."

The next day, Ramirez vented back, claiming he had lost some respect for his manager and noting that Gonzalez had never played in the big leagues.

"It's OK. He doesn't understand that. He never played in the big leagues. That's fine," Ramirez said on May 18.

On the field, the Marlins have had a difficult time patching together their bullpen. In all, 17 relievers have been on the roster so far this season. Florida relievers have walked 104 batters, the fourth-most in the Major Leagues.

There have been inconsistencies at the plate as well. The Marlins' total of 561 strikeouts rank second to Arizona's 666 for the most in the National League.

And last Saturday night, during a 9-8 loss to the Rays in 11 innings, the Marlins were penalized for batting out of order in the bottom of the ninth inning. Gonzalez made three substitution moves, but home plate umpire Lance Barksdale said he heard one.

Gonzalez strongly noted after the game that he properly told Barksdale that Brian Barden would bat ninth and Wes Helms would bat third. But Barksdale had Helms ninth and Barden third. That's what was relayed to Rays manager Joe Maddon, who noted the mix-up after Barden walked to open the inning.

Barden was ruled out for batting out of order. Also that night, the bullpen's struggles were magnified as six relievers combined to walk 11 batters.

Hired to replace Joe Girardi after the 2006 season, Gonzalez has the most wins of any manager in Marlins history with an overall record of 276-279. He was named The Sporting News' Manager of the Year in 2008 after an 84-77 season.

A Miami native, the 46-year-old Gonzalez joined the Marlins after being a third base coach under Bobby Cox with the Braves. Gonzalez said he spoke with Cox on Wednesday morning.

Gonzalez signed an extension through the 2011 season before the 2009 season.

In 2009, the Marlins finished second behind the Phillies in the NL East. Their 87 wins were the third-most in franchise history. Yet, in the final days of the season, rumors surfaced that former Mets and Rangers manager Bobby Valentine was approached to replace Gonzalez.

The Marlins put an end to that speculation a few days later when officials said Gonzalez would return for 2010.

"Decisions on individual personnel cannot supersede our overall goal, which is to win," Loria said. "We believe we can do better and be better. We owe it to our fans to put this team in the best possible position to win. Everyone knows how I feel about winning.

"That's the reason we're making this change. We still have a very long season in front of us, and plenty of time to turn things around. Everyone -- our fans, our team, our organization, and myself -- wants us to win. That continues to be, and will always be, the goal."

The Marlins last switched managers in midseason in 2003, when Jack McKeon was named to replace Jeff Torborg in May. The club went on to win the World Series, beating the Yankees in six games.

Rodriguez, in his eighth season in the Marlins organization, managed New Orleans for the past season and a half. He previously spent two years as manager of Single-A Greensboro (2007-08), two as manager of the Gulf Coast League Marlins (2005-06), and two as hitting coach for Double-A Carolina (2003-04).

Prior to joining the Marlins, he was in the Tampa Bay organization, managing Rookie-level Princeton for three seasons (2000-02) and Class A Hudson Valley for one (1999). He played parts of three seasons with the Yankees and Padres from 1982-85.