Manuel was in his ninth season as the Phillies manager and was having the worst season of his career. The Phillies entered Friday's game against the visiting Los Angeles Dodgers with a 53-67 record.
Philadelphia finished 81-81 last season, the previous worst under Manuel.
"I'm mad because they took the best seat in the house from me," Manuel said in a press conference. "I enjoyed every bit of it."
Manuel was 780-636 in the regular season as the Phillies skipper and 27-19 in the postseason. That includes five National League East championships, two National League titles and a World Series championship in 2008.
Manuel, 69, also managed the Cleveland Indians for three years. His overall managerial record is 1,000-826.
The Phillies offered Manuel a job within the organization, but he said he was not sure if he would accept it or not.
Sandberg, who enjoyed a stellar playing career as second baseman of the Chicago Cubs, had been the Phillies third base coach this season. He previously managed at the Class AAA level.
CBS' "60 Minutes" reported that members of New York Yankees third baseman Alex Rodriguez's inner circle obtained and leaked Biogenesis documents that implicated Milwaukee Brewers third baseman Ryan Braun and Yankees teammate Francisco Cervelli.
The documents were leaked a few days after the Miami New Times reported in January that Rodriguez was using performance enhancing drugs.
Braun and Cervelli's names were edited out of the documents the New Times obtained. However, members of Rodriguez's camp had unedited versions of the documents and leaked them to Yahoo! Sports.
On Friday afternoon, Rodriguez denied he leaked any information regarding the involvement of Braun and Cervelli with Biogenesis.
Boston Red Sox right-hander John Lackey does not believe that Rodriguez should be allowed to play because of his suspension related to performance-enhancing drugs.
"I've got a problem with it. You bet I do," Lackey told the Boston Globe on Thursday. "How is he still playing? He obviously did something and he's playing. I'm not sure that's right. ... It's pretty evident he's been doing stuff for a lot of years I've been facing him."
Jared Remy, the son of Boston Red Sox broadcaster and former player Jerry Remy, was arrested Thursday night on murder and other charges.
Remy was accused of stabbing his girlfriend to death in their apartment Waltham, Mass., apartment while the victim's daughter was home.
Remy was scheduled to be arraigned Friday for murder, domestic assault and battery charges. He also appeared at the court Wednesday after being accused of assaulting the same woman, Jennifer Martel.
A former longtime friend of Milwaukee Brewers slugger Ryan Braun filed a lawsuit against the suspended star outfielder in July, according to ESPN.
The suit by Ralph Sasson alleges that Braun defamed him after he helped Braun during his successful appeal of a steroids-related suspension in 2011.
The Minnesota Twins' Ryan Doumit returned from the concussion disabled list after missing eight days.
The Twins sent Chris Colabello back to Triple-A.
Seattle Mariners manager Eric Wedge, who has been away from the team since July 22 because of a minor stroke, is close to returning.
Wedge hopes to return during the next homestand, which begins on August 23, according to MLB.com.