BOSTON -- The Dodgers and Red Sox are closing in on a blockbuster trade that would send Adrian Gonzalez, Josh Beckett, Carl Crawford and Nick Punto to Los Angeles in a deal that was expected to become official Saturday, a highly placed source said late Friday night.

The Red Sox are reluctantly willing to part with Gonzalez as a means of maximizing financial flexibility.

"Hopefully this deal will go through today," Red Sox chairman Tom Werner said Saturday morning. "If it falls into place, the deal sheds us from tens of millions of dollars of long-term commitments. It gets us great prospects who will improve our major league roster as soon as next year. It brings us a player in James Loney who was 'untouchable' a couple of years ago. It allows us to start over with free agents. We want to win for our fans and we now have huge financial flexibility to improve the team."

Later Saturday, Punto tweeted a photo of Gonzalez, Beckett and himself aboard a plane, with the caption, "#dodgers doing it first class!"

The Dodgers are agreeing to take on the contracts of Crawford and Beckett in order to acquire the slugging first baseman Gonzalez, who will be returning to his Southern California roots.

According to a source, Gonzalez wants to play for the Dodgers on Saturday night and planned to be in the lineup against the Miami Marlins in Los Angeles.

"Excited to get back to Cali and be a part of Dodgertown!" Gonzalez tweeted Saturday afternoon.

Punto, meanwhile, tweeted a farewell to Boston fans.

"Thanks to all the fans of #Red Sox nation, also thank you to all my teammates, coach's and staff," he wrote on his Twitter account.

Beckett (5-11, 5.23 ERA) had become the lightning rod of last September's epic collapse and had won just one of his past 13 starts, while Crawford, after putting up career-low numbers in 2011, played in just 31 games this season because of wrist and elbow injuries and this week underwent Tommy John surgery. The Sox owed Crawford and Beckett a combined $140 million, with close to $130 million owed to Gonzalez.

Beckett had been scheduled to start Saturday night against Kansas City at Fenway. Instead, the Red Sox listed Aaron Cook as the official starter.

Pitcher Rubby De La Rosa will be headed back to Boston as the Dodgers' centerpiece of the deal, sources say. De La Rosa made his first major league appearance of the season Wednesday after undergoing Tommy John surgery about 13 months ago. Also included are first baseman Loney and prospects Allen Webster (right-handed pitcher), Ivan De Jesus (infielder) and Jerry Sands (outfielder), according to sources.

The Dodgers optioned De La Rosa to Double-A Chattanooga on Friday afternoon instead of Triple-A Albuquerque, as originally announced. Gonzalez was scratched prior to Friday's game and summoned to the clubhouse, along with Punto. Loney was a scratch as well, and was called to manager Don Mattingly's office.

"It's a little frustrating because you just think there's so much more there. And I know James thinks there's more there," Mattingly said. "It's hard to have anything really negative to say about James because he's a great kid and he works really hard. He's giving us everything that he's got. It's not a matter of not wanting to or not trying to or not doing the work. It's just not coming out."

The Dodgers still had no announcement after their 11-4 win over the Marlins on Friday night.

"There's still nothing for me to talk about at this point," Mattingly said.

Giving up Gonzalez would be a shocking change of direction for the Red Sox, who in December 2010 traded two of their top prospects -- first baseman Anthony Rizzo and pitcher Casey Kelly -- to acquire the first baseman. Gonzalez is making $21 million this season, the first in the seven-year, $154 million extension he signed in April 2011.