Officials from both teams have yet to confirm the deal. It was first reported by Journal Sentinel beat writer Tom Haudricourt, and Sabathia all but confirmed the deal in a text message sent to ESPN.com reporter Amy K. Nelson.
"I'm good, excited," Sabathia's message said. "It's weird leaving these guys."
Sabathia, the reigning American League Cy Young Award winner, is 6-8 this season with a 3.83 earned run average. The left-hander struggled out of the gate, starting 1-4, but has since steadied and leads the American League with 123 strikeouts in 122 1/3 innings of work.
He last pitched for the Indians on Thursday, allowing four earned runs on seven hits over eight innings of a 6-5 loss to the White Sox. He threw a bullpen session Saturday while the Indians were in Minnesota and is expected to make his first start with the Brewers on Tuesday against Colorado.
Sabathia didn't come without a cost. The Brewers parted ways with LaPorta, considered one of the top prospects in all of baseball. Drafted in the first round by Milwaukee a year ago, LaPorta was hitting .288 with 20 home runs and 66 RBIs with Class AA Huntsville.
"It's kind of flattering to have your name being brought up for one of the best pitchers in the game," LaPorta told the Huntsville Times this week. "There would be no hard feelings one way or another. This is a business, and I understand that."
An All-American first baseman at the University of Florida, the Brewers moved him to left field at the beginning of his professional career. He became expendable when Ryan Braun filled the team's void at that position.
Sabathia turns 28 on July 21 and will become a free agent after this season. The Indians selected him the first round of the 1988 draft and he has been with the franchise ever since. He turned down an extension believed to be worth more than $70 million during spring training.
Melvin wanted to get the deal done before Monday in order to get Sabathia two starts before the all-star break.