ST. LOUIS -- Following through on new ownership's promise to aggressively improve the ballclub, the Dodgers on Wednesday acquired infielder Hanley Ramirez and reliever Randy Choate from the Marlins for pitchers Nathan Eovaldi and Scott McGough.

The Dodgers will pick up nearly $40 million in financial commitment to the sometimes controversial Ramirez, who is signed through 2014.

"The addition of a hitter the caliber of Hanley Ramirez improves our lineup from top to bottom, inserting a proven run producer to go along with Matt [Kemp] and Andre [Ethier]," Dodgers general manager Ned Colletti said. "We're excited for Hanley to begin a new chapter in Los Angeles."

The Dodgers now are determined to bolster their starting rotation. They are essentially in a cat-and-mouse game with the Chicago Cubs and their ace, Ryan Dempster. The Cubs earlier this week reached a trade agreement with Atlanta, but Dempster has no-trade rights and it's believed he will accept a trade only to the Dodgers.

Chicago is believed to want more than the Dodgers are offering. They have reportedly balked at dealing top pitching prospect Zack Lee for a two-month rental, as Dempster can be a free agent after this season.

The need for a starting pitcher is heightened by dealing away Eovaldi, who had been in the rotation since Ted Lilly was injured in May. Lilly could be back in mid-August.

Ramirez is a three-time All-Star, former batting champ and Rookie of the Year. But like another Ramirez the Dodgers acquired four years ago at the Trade Deadline, he comes with some baggage.

He is expected to initially start at shortstop, where Luis Cruz has filled in well in the absence of Dee Gordon, who is on the disabled list but is expected back in mid-August from a torn thumb ligament. When Gordon returns, Ramirez is expected to move to third base.

Changing positions is one of several controversies that have hounded Ramirez in his recent years with the Marlins. He initially balked at making a move when Miami signed free-agent shortstop Jose Reyes last offseason, but third base is where Ramirez has played this year.

Like Manny Ramirez in 2008, however, the Dodgers apparently are convinced this Ramirez will arrive with a positive attitude, be willing to play wherever he's most needed and provide a jolt to the offense, either as a leadoff catalyst or as a No. 5 hitter protecting cleanup man Ethier.

It has not been a good season for Ramirez, a .300 career hitter who is batting only .246 this year with 14 homers and 47 RBIs after hitting .243 last year, when he missed two months with a shoulder injury that required offseason surgery.

He stole 51 bases in each of his first two seasons, but has only 14 this year. His best season was 2009, when he hit a league-leading .342 and finished second for the NL Most Valuable Player Award.

He punched a dugout fan with his right hand July 8 in St. Louis and developed an infection in the resulting cut when he didn't take prescribed medicine. That led to a falling out with Marlins manager Ozzie Guillen and Ramirez became part of an ongoing Miami housecleaning.

Ramirez, 28, is working on a six-year contract that pays him $15 million this year, $15 million next year and $16 million in 2014.

The cost in Eovaldi, however, is substantial. The 22-year-old right-hander is 1-6 after taking over for Lilly, but has been undermined by pathetic run support. His 4.15 ERA is lower than Clayton Kershaw's rookie-season ERA of 4.26.

The Dodgers might also get Rubby De La Rosa back in September. De La Rosa is recovering steadily from last year's Tommy John surgery. If they can't land Dempster by Friday (Eovaldi's next scheduled start), they might call up Allen Webster from Double-A Chattanooga to make the start.

The 36-year-old Choate has a 2.49 ERA in 44 games and gives the Dodgers a second lefty reliever to go with Scott Elbert. The Dodgers will be his fifth organization; he played for the Yankees while current Dodgers manager Don Mattingly was a Yankees special instructor.

McGough, 22, was the club's fifth-round selection in the 2011 First-Year Player Draft out of the University of Oregon and was 3-5 with a 3.99 ERA and five saves in 35 relief appearances for Single-A Rancho Cucamonga this year.

The Dodgers will move reliever Todd Coffey to the 60-day disabled list to make room on the Major League roster. A spot on the 25-man roster will open up when the Dodgers place Adam Kennedy on the 15-day disabled list with a strained right groin.