San Francisco traded the veteran to the Brewers for two minor leaguers, with both clubs waiting until after the teams played Sunday to announce the swap. That, in fact, was per Durham's request as he didn't want to suit up for his first game for Milwaukee against the Giants.
"Personally it was out of respect for the guys in this locker room," Durham said, saying his goodbyes in the Giants' clubhouse. "It really was a stipulation I asked for."
An emotional Durham could only stand to be in the Giants' dugout for a few innings during the series finale against Milwaukee, but was prepared to make the switch right afterward and head to St. Louis with the Brewers. The 36-year-old second baseman, in his sixth season with San Francisco, had to approve the deal.
"He's a veteran guy that can come in here and help our club," Milwaukee general manager Doug Melvin said. "We're trying to add as many good players as we can. We're trying to win this thing."
Durham is hitting .293 for the San Francisco Giants, with an on-base percentage of .385, and in theory, he could help the Brewers as a utility player. But it is also very possible that he will press Rickie Weeks, the Brewers' everyday second baseman to this point, for playing time.
Weeks is hitting .218 with eight homers, and Milwaukee ranks dead last among all teams in batting average for second baseman (.222).
Brewers manager Ned Yost said initially Durham would play a couple of days a week, with Weeks remaining the starter at second.
"He brings a guy that is a really, really good offensive player, a switch-hitter who can hit good pitching," Yost said of Durham. "He's a solid offensive player and he's a veteran guy that's really good with younger players. He fits right into what our veterans bring every day into the clubhouse."
San Francisco received left-hander Steve Hammond and outfielder Darren Ford for the second baseman. Milwaukee was also given cash considerations in the deal.
The seriousness of the Durham talks between the Giants and Brewers was reported by the San Francisco Chronicle on Saturday.
Giants GM Brian Sabean met with Durham during Saturday's game about the trade, which came together quickly after Sabean spoke by phone with Melvin while both were in New York for the All-Star Game.
Durham was a late arrival to the ballpark on Sunday, getting to the clubhouse in a rush about 2 hours before the game with a bag on his shoulder.
"I've got to do a few things right now," he said before the Brewers swept the Giants 7-4, but never emerged at his locker before the game while the clubhouse was open to the media.
Milwaukee is three games back of NL Central-leading Chicago and one behind the Cardinals as they head to St. Louis.
"I think ownership and upper management have shown a commitment to winning and winning now, so it's very exciting to us," Milwaukee left fielder Ryan Braun said.
Durham is in the final season of a two-year, $14.5 million contract.
"I understood it," Durham said of the trade. "I know this organization, they're trying to go young and they're rebuilding for the future. It didn't shock me."
Buster Olney is a senior writer for ESPN The Magazine. Information from The Associated Press was used in this report.