It's unclear what the Padres will receive in return for the 42-year-old Maddux. MLB.com reported on Monday night that the Padres would receive two players to be named later. The trade, which was first reported by the Los Angeles Times, was expected to be announced Tuesday.
According to ESPN.com's Jayson Stark, no deal had been reached Monday night, but conversations are ongoing. Dodgers spokesman Josh Rawitch and general manager Ned Colletti would not confirm the deal to the Times either.
This year, the Dodgers and Padres discussed a deal for Maddux before the July 31 deadline, but talks fell through.
"I would say nothing ever got real close," Padres general manager Kevin Towers said then. "We let it be known with the Dodgers, that was the one ballclub he had interest in going to, that any deal we were going to do was going to be the best baseball deal we could do and it wasn't going to be a financial deal to try to move dollars. We just weren't happy with the prospect we would be getting back, and we chose to hold onto him."
A four-time Cy Young Award winner, Maddux has a full no-trade clause in his contract and agreed to waive it. He joined the Padres in 2007 and returned this season for a $10 million, one-year deal.
Maddux has a 3.99 ERA this season but is only 6-9 for a Padres team that has languished in last place in the weak NL West. The Dodgers moved into a first-place tie with the Diamondbacks in the division on Sunday.
Los Angeles had a need for another starter, however, after putting right-hander Brad Penny on the disabled list last week.
This would be Maddux's second stint with the Dodgers. The Cubs traded him to Los Angeles at the trade deadline in 2006 and he went 6-3 in the regular season for the Dodgers. Los Angeles lost to the Mets in the divisional series.
The Dodgers completed a trade for Ramirez with the Red Sox on Aug. 1, and he has batted .421 with six homers and 21 RBIs for Los Angeles.