The move helps the Cubs trim some payroll although they also will send $2.5 million to the Dodgers in the transaction. Theriot was making $2.6 million this season and is owed about $900,000 for the rest of the season, while Lilly is still owed $4.3 million for the remainder of the year.
"[The money] was something we felt wasn't going to be the detriment," Cubs general manager Jim Hendry said. "We put a value on the players we got back. Obviously, the money that Teddy had coming and Ryan was already budgeted for this year. ... If it cost us some of the money to get a better package, that's what we did."
Lilly (3-8, 3.69 ERA) was in the last year of a four-year contract. Right-hander Thomas Diamond, who was pulled after throwing four innings on Thursday for Triple-A Iowa, will make his Major League debut on Tuesday for the Cubs, replacing Lilly in the rotation.
An All-Star last year, Lilly's problem this season was simply a lack of run support. He had the lowest in the Major Leagues.
"I think I'm going to a really good place and to a team that has aspirations of winning the World Series, and that's a fortunate thing for me to be a part of," Lilly said.
The Dodgers began play Saturday seven games back in the National League West. Lilly will be returning to the team that drafted him in 1996. He talked to the Dodgers' equipment manager on Saturday, and the lefty said it's the same person who handed him his first uniform during Spring Training games.
"It's pretty amazing how this has come full circle," Lilly said.
Chicago was special, too.
"I couldn't ask for a better place to play, teammates to play with, fans to play for," Lilly said. "All the way from the coaching staff to the front office, I can't say enough."
He had a partial no-trade clause, and the Dodgers were one of the teams he would approve.
"It's not something I'm overly excited about," Lilly said about leaving the Cubs. "I'm going to miss a lot. But when I go over there and I put a Dodgers uniform on and I meet my new teammates and start competing with them, I'll really enjoy it."
This is the last year of Lilly's contract. He would consider coming back, but there apparently have been no talks between the Cubs and the lefty about extending his contract.
"I think I voiced my opinion as to what I'd prefer, but there are reasons that go into it," Lilly said. "I would imagine money is one of them."
The two sides never exchanged dollar figures for a possible extension.
"Anybody would always want Ted Lilly if he's healthy and going good," Hendry said. "I think he'll have the chance to go out and test the market. He's 34 years old, but he's obviously still pitching at a good level. We would never close the door on that. For now, he has to do what's best for the Dodgers and help them get to the postseason, and we'll worry about the offseason in the offseason."
Said Lilly: "Obviously, this organization is commited to win. I would imagine they'll do what's necessary to put this club in that position again in 2011. One thing I've learned is you can't get too far ahead of yourself and try to predict what's going to happen down the road. I seem to benefit from just trying to keep my mind focused on one thing at a time and my next start kind of thing."
The Cubs began play Saturday 11 games back in the NL Central.
"I don't think this is how any of us would've drawn it up," Lilly said. "[Hendry] didn't have a lot of choices. We would all prefer to be buyers and to be acquiring pieces but this is what it's come to."
Theriot, 30, lost his starting shortstop job to rookie Starlin Castro in early May and was moved to second. He was batting .284 with 10 doubles, two triples, one home run and 21 RBIs in 96 games.
In February, Theriot and the Cubs went to arbitration, and the infielder lost his case but still earned a significant raise. He made $500,000 in 2009 and was seeking $3.4 million in arbitration. It was the first hearing under Hendry and the Cubs' first since 1993.
DeWitt, 24, is expected to join the Cubs on Sunday in Denver. He was batting .270 in 82 games with 15 doubles, four triples and one home run. He is a career .262 hitter with 31 doubles, six triples and 12 home runs in 230 games covering the past three seasons with the Dodgers. He has played second, third and shortstop. DeWitt was making $410,000 and is under team control through 2014.
Dodgers manager Joe Torre said they were not trying to move DeWitt.
"He was the price tag," Torre said.
DeWitt said goodbye to his teammates in the clubhouse before Saturday's game.
"It's sad in a way," DeWitt said. "It's definitely a tough situation for me. I've worked hard with these guys going far back. It definitely came as a complete shock, but it's part of the game. I look forward to the opportunity there. Chicago is probably my favorite place to go on the road, and it's definitely close to my family [in Missouri]."
DeWitt was batting .222 against left-handed pitchers and .280 against right-handers. This month, the infielder was hitting .295 in 21 games and had two steals. Cubs special assistant Greg Maddux, who played with DeWitt when he was with the Dodgers, gave the infielder high marks.
"We think he's a real solid player," Hendry said. "We liked him for years when he first entered professional baseball. He's only 24 years old, and his better days are ahead of him."
DeWitt may help the Cubs in the division. He's batting .313 against NL Central teams, including .429 against Pittsburgh.
The Cubs also receive Minor League right-handed pitchers Kyle Smit and Brett Wallach from the Dodgers. Smit, 22, was 5-3 with six saves and a 2.35 ERA in 37 appearances between Class A Inland Empire and Double-A Chattanooga. Wallach, 21, son of former big league player Tim Wallach, was 6-0 with a 3.72 ERA in 17 starts for Class A Great Lakes, striking out 92 in 84 2/3 innings.
Carrie Muskat is a reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.