The hemming and hawing from Fielder on Sunday after All-Star rosters were announced strongly suggested he was going to take part. On Monday, it became official when AL Derby captain Robinson Cano named him to the team for the annual slugfest, set to take place next Monday night on ESPN at 8 p.m. ET at Kauffman Stadium in Kansas City.
"Robinson asked me if I wanted to do it and I said, 'Yeah,'" Fielder said Monday night. "It's fun. I don't know if it's life or death, but I'm going to do my best."
It'll be the third Home Run Derby for Fielder, who has a flair for clearing the fences when it takes place at a division rival's ballpark. He won the 2009 event as a Brewers slugger when it was held at Busch Stadium in St. Louis.
Fielder served as the National League captain at last year's Derby and made it to the second round before losing out to eventual champion Cano and runner-up Adrian Gonzalez.
Now, he crosses what used to be enemy lines to join the AL squad where he expects it to be quite different.
"It's not the same. It's going to feel a little different," he said. "But it's just I'm in the American League now, so it is what it is."
Fielder had indicated his interest remained over the past couple of weeks when it became apparent his lead in All-Star balloting among AL first basemen was going to stick. The fact that he changed leagues had no impact on him. He didn't confirm it when asked Sunday or Monday, but the coy nature of his answers gave a pretty strong indication he was taking part.
Fielder and Cano will join two-time AL home run champion Jose Bautista of the Blue Jays and Angels sophomore slugger Mark Trumbo on the team. Among those left off was Fielder's teammate, Miguel Cabrera, who took part in the 2010 Derby but wasn't sure when asked Sunday if he would participate this year.
Fielder is the ninth Tiger to take part in the Derby. They've combined for 33 home runs, but no titles. The past three Tigers participants -- Cabrera (2010), Brandon Inge (2009) and Magglio Ordonez (2007) -- have combined for 14 homers, with Cabrera accounting for 12.
For each of those three, the batting-practice pitcher was bullpen catcher Scott Pickens. Fielder didn't say who would serve as his pitcher, but he said he's thought about it.
"I got an idea," said Fielder, who wasn't ready to reveal his choice just yet.
With a win, the 28-year-old could become the second player in Derby history to win the event more than once -- Ken Griffey Jr. did it three times in in 1994, '97 and '98. However, Fielder would be the only player to do it in two different leagues.
The thought is that the event can mess with your swing, but Fielder said he wasn't a believer in that. Whereas some do hit slumps following the All-Star break, his splits were about the same in both years.
In 2009, he hit .283 with 24 homers in the second half -- two more than in the first half. In '11, he hit six fewer home runs, but his average was four points higher at .301.
"I swing like that every time. I swing hard," he said. "I don't know if it benefits me or hurts me. I just know that all it is is a show."
Anthony Odoardi is an associate reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.