A trade that had become inevitable over the past few weeks turned into a reality Sunday.

The Boston Red Sox sent hard-nosed third baseman Kevin Youkilis, one of the last links to the 2004 World Series champs, to the Chicago White Sox for utilityman Brent Lillibridge and Triple-A right-hander Zach Stewart. The Red Sox also agreed to pay $5.5 million of the nearly $7 million remaining on Youkilis' contract.

The deal became apparent in the bottom of the seventh inning of Boston's 9-4 win over the Atlanta Braves when Youkilis was lifted for a pinch-runner, triggering a stirring Fenway Park farewell that included a curtain call and one more boisterous "Yoooooouk!"

"It's an emotional time for everyone -- for Kevin, for his teammates," general manager Ben Cherington said after the White Sox concluded their game in Chicago and the trade became official. "Kevin has been here for a long time and has been a great player and played hard every inning he's been out there."

But everyone, including Youkilis, realized the time had come for a parting.

A three-time All-Star, Youkilis has been overrun by injuries in the past two seasons. Since returning last month from a three-week stint on the disabled list, his production has slid to the depths of a .233 batting average with only four homers, 14 RBI and an un-Youk-like .315 on-base percentage.

Youkilis also has clashed with manager Bobby Valentine. And given the rapid emergence of rookie Will Middlebrooks, Cherington spent the past few weeks listening to offers for Youkilis, knowing the 33-year-old's value rarely had been lower.

"We were trying to find a resolution that worked for everyone," said Cherington, who took minimal pause at trading Youkilis within the American League to a potential wild-card competitor. "Kevin's been an everyday player for pretty much his entire career. With the way Middlebrooks has been playing, Middlebrooks needs to be in the lineup. Once we came to that conclusion, we talked about it and decided that if there was a trade that made sense for us and for Kevin and everyone involved that we would pursue that."

Stewart was a key piece to the deal, according to Cherington. Although the 25-year-old right-hander will report to Triple-A Pawtucket and already has been traded by Cincinnati and Toronto, the Red Sox believe he can add depth to the rotation, even though he has a 5.92 ERA in 31 games for the White Sox over the past two seasons.

Lillibridge, a .215 career hitter, will join the Red Sox and provide versatility. In five seasons with the Braves and White Sox, he has played every position except catcher.

Youkilis left the clubhouse before the media was permitted to enter after the game. But his Red Sox legacy speaks for itself. In nine seasons with the team, he batted .286 with 133 home runs and 564 RBI. He was a three-time All-Star and finished third in the MVP voting in 2008 when the award was won by teammate Dustin Pedroia.

"It's tough," Pedroia said. "Youk's a guy I've played with my whole career here. I know how hard he's played, and he's given everything he's had in every game he's ever put on the Red Sox uniform. He pushes me every day. I want to go out and play hard just like he does."

Said infielder Nick Punto, "You feel for him, the way it went down. Actually, I'm excited for him. I think he's going to be happier, being closer to (his hometown of Cincinnati). He's having a baby. He can clear his mind and start fresh."