The deal was agreed upon late Monday afternoon, but at that time, medical records weren't complete. So the trade was consummated on Tuesday.
As part of the package, Florida obtained Minor League right-hander P.J. Dean and second baseman Jake Smolinski.
Of the three, Bonifacio is the most big league-ready, and the Marlins feel the 23-year-old speedster can become an everyday player. A natural second baseman, the switch-hitter from the Dominican Republic will get a chance to earn the starting third-base job in Spring Training.
"We talked a lot at the end of the season and into this offseason about pitching, speed and defense," Marlins president of baseball operations Larry Beinfest said. "I think Bonifacio fits that to a 'T' as far as speed and defense. We see him as an above-average fielder and a well-above-average runner. He fits the mold of what we're looking for."
Admittedly, the trade was partly driven by money. Team owner Jeffrey Loria has set a payroll believed to be between $30-$35 million. Olsen and Willingham, both arbitration-eligible for the first time, project to make around $5 million collectively.
"We have a working payroll from Jeffrey," Beinfest said. "It is an increased payroll from a year ago, and we are just trying to make sure of our allocation within that payroll, [so that] we're as competitive as possible. So money does matter certainly in these transactions. We want to make sure our allocations are directed in the right places."
In 2008, the payroll was $22 million. Florida now has 12 arbitration-eligible players.
This is the second major trade the Marlins have made since the World Series ended. On Oct. 30, first baseman Mike Jacobs was dealt to the Royals for reliever Leo Nunez.
The upside for Bonifacio is the fact that he is terrific defensively, drawing a comparison to former Marlins Gold Glove Award winner Luis Castillo. Bonifacio has great range, and he is slick at turning the double play.
Because of his speed, the Marlins envision Bonifacio eventually to be a leadoff batter. The organization also likes the prospect of having three blazing baserunners: Bonifacio, Hanley Ramirez and Cameron Maybin.
At least for now, though, Beinfest said Bonifacio will get his strongest look at third base. The plan is to stick with two-time All-Star Dan Uggla at second base. Beinfest didn't rule out the possibility of changing Uggla to third, but for now, that isn't the objective.
"We'll take a look at [Bonifacio] in Spring Training at second, short and third," Beinfest said. "We're specifically going to look at him at third base. We definitely feel he has enough arm to play over there.
"Not to open a can of worms, but Danny is a two-time All-Star at second. We've seen above-average defense with him. We think there is a comfort zone with he and Hanley up the middle. It's something we'll keep open, but we're real happy with the way Danny has performed at second."
Third base will have plenty of competition in Spring Training. Jorge Cantu is the favorite to start at third, but there remains a chance that he could be moved to first base, where he'd compete with Gaby Sanchez.
Prospect Chris Coghlan, who has been playing second base in the Minor Leagues, will work at third in Spring Training. Veteran Wes Helms and Dallas McPherson also will get a look at third.
As for replacing Willingham in left field, Beinfest said Cody Ross will be the front-runner. Maybin projects to be in center field, with Jeremy Hermida in right field. Brett Carroll, who will get a look at a backup outfield spot in Spring Training, right now is nursing a broken wrist. Carroll was struck in the hand by a pitch while playing winter ball in the Dominican Republic.
The biggest question surrounding Bonifacio is his offense. In 49 games with the Nationals and Diamondbacks, he hit .243.
If Bonifacio can get on base, he has tremendous speed, and he's a threat to steal bases.
"The name Luis Castillo has come up," Beinfest said when referring to Bonifacio. "He's obviously one of the all-time great Marlins, and it's tough to compare people. But that's one of the names that has been brought up at times. I think you're looking at that type of player.
"We're not expecting power. We did not trade for power. We want the speed. We want the defense. We like the way he plays the game. He plays with a lot of enthusiasm. He has a hop to his step. We like that type of player."
The Marlins plan to work with Bonifacio on improving his bunting, and they feel he can hit from both sides of the plate.
Bonifacio opened 2008 in the Diamondbacks' farm system. He was traded to Washington in July as part of the Jon Rauch trade.
Dean, a 20-year-old right-hander, went 4-1 with a 1.57 ERA in 10 starts for Class A short-season Vermont in the New York-Penn League. He threw 46 innings, striking out 34 while walking 16.
The acquisition of Dean continued a pattern the Marlins strive for in just about every trade they make. The team typically tries to bring back pitching, no matter the deal.
That was the case in the Oct. 30 trade with Kansas City, as Nunez projects to factor into a late-innings setup role.
Dean, a 6-foot-3, 175-pounder, was a seventh-round pick out of New Caney High School in Texas in 2007. His fastball has been clocked between 90-94 mph.
Smolinski, a second-round pick in 2007, is a 19-year-old out of Boylan Catholic High School in Rockford, Ill. He appeared in 77 games at the low Minor League level this past season, including 24 with Vermont. In 98 at-bats in the New York-Penn League, he hit .306.
Smolinski underwent knee surgery recently, and he is expected to miss six to eight months.
The Nationals showed interest in Olsen for more than a month, and the deal was close to being finalized last Wednesday at the General Managers Meetings in Dana Point, Calif.
Beinfest wouldn't speculate on how many more moves the Marlins would make. It is widely believed that closer Kevin Gregg, who made $2.5 million in his second season of arbitration, will be dealt sometime before or at the Winter Meetings in Las Vegas.
"We're dealing with the challenges we have within our payroll, and hopefully, we're getting the right pieces," Beinfest said.