On Monday, they reached agreement with the Nationals on a five-player trade that is expected to be announced on Tuesday, according to an industry source. Neither team has confirmed the trade.

Florida will send left-hander Scott Olsen and left fielder Josh Willingham to the Nationals for second baseman Emilio Bonifacio and Minor League pitcher P.J. Dean. Other reports have 19-year-old middle infielder Jake Smolinski added to the deal.

Once completed, it will mark the Marlins' second trade since the World Series ended. On Oct. 30, they dealt first baseman Mike Jacobs to the Royals for reliever Leo Nunez.

Olsen and Willingham are preparing to head to Washington, where they are expected to be introduced at a news conference on Tuesday. Both players are eligible for arbitration for the first time.

"My initial reaction is I would be back," said Willingham, a 17th-round pick by the Marlins in 2000. "You knew that moves were going to be made, but you didn't know who."

Speaking from his home in Florence, Ala., Willingham received a call late Monday afternoon from Marlins president of baseball operations Larry Beinfest saying he was going to Washington.

The Marlins project their payroll to be between $30-35 million next season. The team entered the offseason with more than 15 players eligible for arbitration.

Like Olsen and Willingham, Jacobs also is up for arbitration.

Since 2006, the Marlins have been going with a youthful roster that made great strides this past season. Florida finished third in the NL East with an 84-77 record.

"We made huge strides in '06, and in '07, we were hurt by injuries," Willingham said. "In '07, we got some key people back. It's unfortunate we all got a little pricy at the same time."

After hearing word that he was being traded, Willingham called veteran Aaron Boone, a free agent who played for the Nationals in '08 after spending '07 with the Marlins. Willingham joked with Boone, telling him he had to re-sign with Washington.

"It's exciting," Willingham said. "But at the same time, you're going to miss a lot of the relationships you've developed."

Olsen, a left-hander, was 8-11 with a 4.20 ERA in 33 starts in 2008, logging a career-high 201 2/3 innings. Willingham, meanwhile, was bothered by a back injury that caused him to miss 50 games in the first half. The left fielder appeared in 102 games, and he batted .254 with 15 home runs and 51 RBIs.

One of the Marlins' offseason objectives has been to improve defensively.

Bonifacio is a 23-year-old second baseman from the Dominican Republic. He appeared in 49 games for Washington, and in 169 at-bats, he batted .243 with six doubles and five triples. A switch-hitter at the plate, Bonifacio has tremendous speed, and his defense has drawn comparisons to former Marlin Gold Glove winner, Luis Castillo.

The addition of Bonifacio raises questions about All-Star second baseman Dan Uggla. Uggla projects to make about $5 million in arbitration. If the Marlins retain him, they could shift him to third base, and slide third baseman Jorge Cantu to first base.

Dean is a 22-year-old right-hander who pitched for Vermont of the short season New York-Penn League, going 4-1 with a 1.57 ERA in 10 starts.

Like Dean, Smolinski played for Vermont this past season. Smolinski will not be available to play for a while. He suffered a knee injury and is expected to miss six to eight months.