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Rumors that Kimi Raikkonen was headed to NASCAR became reality Saturday when the former Formula One world champion signed with Kyle Busch Motorsports.

The Finn will make his NASCAR debut May 20 driving a KBM Toyota Tundra in the Trucks Series race at Charlotte Motor Speedway.

"I am really excited to have the opportunity to start my venture into NASCAR with Kyle Busch Motorsports," Raikkonen said in a statement.

"Kyle is one of the best in NASCAR, and being able to draw on his knowledge will be a valuable asset as I make my transition to a new form of racing. He has put together an experienced team that builds fast race trucks. I look forward to being a part of a team that has proven to be a winner on and off the race track."

Raikkonen spent nine years in Formula One, driving for Sauber, McLaren and Ferrari. He was teammates with current NASCAR star Juan Pablo Montoya at McLaren.

Busch said Saturday that Raikkonen will drive between three to five races for KBM, with the schedule beyond Charlotte undecided. Raikkonen is responsible for the sponsorship money, and Busch deferred to Raikkonen's management team on funding issues.

If Raikkonen wanted to do more races and could pay for them — Busch suffered financial difficulties in last season's debut as a team owner — Busch said KBM could accommodate a more extensive schedule.

"I have yet to speak to Kimi myself, but apparently there's an interest with him that he wants to run in NASCAR and he's been shopping around to quite a few teams, and apparently we won the war," Busch said. "Kimi, from what I understand, was real adamant with wanting to work with me and our teams and put a together a deal.

"I don't know where the money is coming from. My contract is with Kimi himself. I do know that there's three sponsors involved, I'll wait for their press release to see if they announce who they are, but there is money backing him."

Raikkonen had 18 wins, 62 podium finishes and won the 2007 Formula One championship. He's currently racing for the World Rally Car Championship with his own team, ICE 1 Racing.

Four-time NASCAR champion Jeff Gordon smiled with excitement when told Raikkonen had signed with Busch.

"I can't believe it. I couldn't believe it when Juan Pablo made that announcement," Gordon said. "So many things going through my mind. I think it says a lot about NASCAR that somebody like him is considering coming here. I admire him for wanting to take the step and go Truck racing and not just jump in a Cup car.

"I think, obviously, the word is out there to the best drivers in the world if you think you are just going to come in here and jump in a Cup car and be competitive, you are kidding yourself."

Montoya on Friday questioned Raikkonen's choice to debut at Charlotte. Montoya's stock car debut was an ARCA race at Talladega, and former F1 driver Scott Speed followed the same plan.

Nelson Piquet Jr., who currently drives in the Trucks Series for Kevin Harvick Inc., made his debut in an ARCA race at Daytona. All three drivers chose superspeedways, where handling is less important than at Charlotte.

Busch said he didn't pick Charlotte for Raikkonen, who will likely select his races based on his rally schedule. The Trucks race at Charlotte falls between the rally races at Sardinia and Argentina.

"It's a big deal for him to be able to fit it in when he can, and Charlotte, they actually picked Charlotte," Busch said. "For whatever reason, they were adamant about Charlotte and running that race. It will be good for him to get his feet wet, and I think if he can run top-20, top-15, that would be a success."

Busch's crew from his flagship No. 18 truck will work with Raikkonen at Charlotte, while crew chief Rick Ren and Busch will recruit volunteers for his entry. Busch is the defending race winner.

Raikkonen will get his first test with KBM Monday at Gresham Motorsports Park in Georgia. Busch has not decided if he'll attend the test.

Piquet, the most recent driver to leave F1 for NASCAR, said he didn't know about Raikkonen's interest.

"He's a bit of a funny guy. He changes his mind like he changes his underwear. You can never know," Piquet said. "Maybe he can stay doing this for 1-2 years. Maybe he can do three races and gets fed up. You never know with Kimi."

Piquet said he's exchanged emails with Raikkonen and has plans to see him when he gets in the country.

Montoya and Gordon both lauded NASCAR for its ability to attract drivers from different forms of motorsports, but Piquet said there's still fear in F1 of the unknown.

"Nobody was brave enough to say let's go to NASCAR. It's a different culture. A whole different culture," Piquet said. "All ovals and heavy stock cars. I think they're scared of doing it. If you ask anyone on the grid, they would love to do a race. But they're just scared of doing it.

"They're scared of taking that whole step of moving to America and being part of this culture and family. Everybody just doesn't know what's on the other side of the hill."