In return, the Marlins are receiving outfielder Cameron Maybin, lefty starter Andrew Miller and four prospects, in exchange for the final two players from the Marlins' 2003 World Series championship squad.
Included in the deal are catcher Mike Rabelo and pitchers Dallas Trahern, Eulogio De La Cruz and Burke Badenhop.
The trade became a reality after the necessary paperwork and medical reports were completed. That took from early Tuesday night until mid-afternoon Wednesday.
In Detroit, Willis and Cabrera will rejoin a few of their former teammates. Ivan Rodriguez was on Florida's 2003 World Series championship team, while closer Todd Jones was with the Marlins in 2005.
"They've got a lot of [Marlins] alumni," said Willis, who is vacationing for a few days in Mexico. "They've got some good guys over there, some good veterans I've played with."
While he is moving on, Willis said he will become a Marlins fan from a distance.
"I'm very happy with the time I've spent in Florida," Willis said. "They have some great players in Florida. I'll be rooting for those guys."
For Willis, this is the second time in his professional career that he has been traded. As a prospect for the Cubs in 2002, the D-Train was dealt to Marlins shortly before Opening Day.
"Like I said the whole time, it's all a business," Willis said. "I have been on the trading block for kind of a world record for the last three years. They found a deal suitable for both sides, so I'm happy to go over there and try to do my thing."
The Tigers swooped into the sweepstakes for Cabrera and Willis on Tuesday and put together a package of players that the Marlins felt too tempting to pass up.
While the Marlins are dealing two of the most popular players in team history, they are bringing in six top-flight prospects. Three of them are likely to be on the Opening Day roster.
What this trade does is address several of Florida's needs. The Marlins headed to the Meetings hopeful of acquiring a starting pitcher, a catcher and a center fielder.
Maybin and Miller were both first-round Draft picks of the Tigers, Maybin in 2005 and Miller in 2006. Both have tasted the Major Leagues. Rabelo, meanwhile, becomes a candidate to start at catcher.
Maybin and Miller clearly are the centerpieces.
Maybin, 20, made his debut in August and appeared in 24 games, hitting .143 with one home run in 49 at-bats. However, he made a rapid rise through the Tigers system, batting .304 with 10 homers in 83 games for Class A Lakeland before making a brief stop at Double-A Erie.
Maybin immediately becomes the front-runner to be the Marlins' starting center fielder.
Miller, 22, made 13 starts for Detroit last season, going 5-5 with a 5.63 ERA. In 78 Minor League innings in 2007, he allowed 71 hits and struck out 61 batters. He was drafted out of the University of North Carolina.
The left-hander has a strong chance to begin in the rotation.
Trahern, a right-handed starter, pitched for Team USA this fall. De La Cruz, who possesses a 100-mph fastball, is considered a candidate to either start or relieve.
"I'm pretty excited," Trahern said. "I love the Tigers organization, but this is a new door opening for me. But I haven't heard anything yet. I'm a little surprised by this. I wasn't aware of this. I wasn't aware that we were in the Cabrera/Willis talks."
Badenhop, another right-handed starter, was selected as the Tigers' Organizational Pitcher of the Year by MiLB.com.
Cabrera and Willis were both rookies on the Marlins' 2003 title team. Both are eligible for arbitration through the 2009 seasons. Cost has become a concern for Florida, making the two All-Stars expendable.
Cabrera is a four-time All-Star who comes off a season in which he batted .320 with 34 home runs and 119 RBIs. The 24-year-old made $7.4 million this past season and he is in line to earn more than $10 million in 2008.
Willis is coming off a 10-15 season with a 5.17 ERA. While the D-Train, who made $6.45 million in 2007, is coming off his worst season, he compiled 205 1/3 innings, marking his third straight 200-plus-inning season.
Willis, who turns 26 in January, is Florida's all-time leader in victories. The left-hander, who won the 2003 National League Rookie of the Year Award, has a 68-54 career mark with a 3.78 ERA. In 2005, he became the Marlins' first, and only, 20-game winner, as he topped the Major Leagues with a 22-10 mark while posting a 2.63 ERA.
Willis was an All-Star in 2003 and '05.
"I was very proud and happy about my time in Florida," Willis said. "[Team owner Jeffrey] Loria was wonderful to me and the opportunity was great, but at the same time, I understand it's a business. I'm also happy I'm wanted somewhere other than Florida. I'm going to go out there and do the best I can for the team I'm with now."
Cabrera, meanwhile, is the only Florida player to be selected to four All-Star Games. A budding superstar, the Venezuela native became the third-fastest player in MLB history to reach the 500-RBI mark in 2007. The slugger has a .313 career batting average, along with 138 home runs and 523 RBIs.
He established career highs with his 34 homers and 119 RBIs this past season. Cabrera has driven in more than 112 runs in four straight seasons.
In 2003, Cabrera was a 20-year-old who batted cleanup in the World Series.
For weeks, the Marlins had been in intense talks with the Angels and Dodgers regarding Cabrera. And on Monday, the White Sox became a factor in the Cabrera chase.
By late Tuesday morning, however, the Tigers had emerged as the front-runners by showing interest in both Florida stars.
Cabrera's bat now will fit in the middle of the Tigers' order, which includes slugger Magglio Ordonez. The two natives of Venezuela are close friends.
"It's great to have him," Ordonez told LasMayores.com in Spanish. "At this moment, he is the best Venezuelan player in baseball. He is a fighter, a competitor. He knows how to win.
"This makes our team much better. Last year we lost because we had too many injuries. With Miguel and Dontrelle, we are going to be the favorites to win the division."