Kyle Busch has been one of the biggest names potentially shaping up as a free agent at the end of the current season, but he's firmly squashed speculation that he might be about to change teams by agreeing terms with Joe Gibbs Racing for a multi-year contract extension.

"I'm really excited about that being a part of JGR and this family for a long-time to come," Busch said as the new deal was formally announced on Thursday.

The exact duration of the new contract wasn't revealed, but it means Busch will stay with JGR until at least the end of 2015. Busch originally joined the team in 2008 after spending his first three seasons in Sprint Cup competition with Hendrick Motorsports.

"We always start a year early, we never go to the last year," team owner Joe Gibbs said about why the deal was being announced well in advance of the end of Busch's existing contract. "You have a gifted athlete and other people are going to go after him, which happens."

And Busch himself admitted that he'd gone window-shopping at the end of 2012 to see what else might be on offer.

"I did meet with some other teams and they were very interested and there were some very nice, lucrative deals that were out there to pursue," said the 27-year-old. "Ultimately what it comes down to is relationships and things that you've developed over the last five or six years."

Gibbs admitted that Busch could probably have got more money if he'd chosen to go elsewhere even in an austerity period of tightened belts within the sport, but JGR clearly stretched itself as far as team funds were available in order to keep Busch behind the wheel.

"The good news is we signed him to a long-term deal, the bad news is we now work for him - and we're broke!" quipped team president JD Gibbs.

2012 was not a good year for Busch, and he himself dubbed it his "worst season ever" after missing out on making the end-of-season Chase by just three points. In addition, there had been some growing niggles within the driver/team relationship which clearly had an effect.

The team wanted Busch to stop spreading himself so thin over Nationwide and Truck Series races and instead focus on his Sprint Cup season, while Busch himself made waves by setting up and driving for his own Nationwide team which put him in direct composition with JGR's own efforts in the second-tier series. However, the new contract negotiations appear to have resolved those issues moving into 2013.

"We didn't want to prove it, but we kind of proved that [skipping Nationwide and Truck] didn't do anything [for Cup]," Busch said. "We tried something and it didn't work."

"There were certainly some benefits to him not driving," insisted Busch's Cup car crew chief Dave Rogers. "I had access to him during the Nationwide race, other drivers didn't get mad at him because he jumped them on a restart or crazy stuff like that that tends to happen.

"But the con that you gave up is Kyle really loves to race," Rogers admitted. "He is the very happiest when he is sitting in the seat driving the car to its limit. The negative to him not driving [is that] he just wasn't as excited to go to the racetrack each weekend because he was only going to drive one time instead of three."

"He thrives on it," Joe Gibbs conceded. "He kind of took a year where he didn't do as much and now his schedule is going to be crowded. But I don't think it is something that he can't handle."

The solution that the the two parties have arrived at is for Busch to drive JGR's car in 25 races this year's Nationwide Series, expanding his number of races and eliminating the direction competition. Busch brings with him the car number (#54) and the Monster Energy drinks sponsorship from last year's Kyle Busch Motorsports entry.

"Part of the agreement is that I've brought over the Monster [sponsorship deal," Busch explained. "Joe was adamant about me racing his Nationwide cars out of his place at Joe Gibbs Racing, so as part of my deal I'll be rejoining forces with [JGR Nationwide crew chief] Adam Stevens. We'll fill out the rest of the races with some younger talent to get out there for us," he added of the remaining eight races in the Nationwide schedule that he'll sit out.

Kyle Busch Motorsports will still run a separate car for Parker Kligerman in 2013, but as part of the joint reconciliation the team will now be supplied engines by the JGR workshop. JGR have also signed off on Busch returning to Truck Series competition with KBM for 10 events, or nearly half the season.

Busch will once again be joined at JGR by Denny Hamlin, and also by new team signing Matt Kenseth. Joe Gibbs said the off-season chemistry between the trio had been exceptionally good.

"I was thinking this whole offseason they got along great and everything, but that's going to last until about the first time they get alongside each other up front!" Gibbs laughed. "And I'm going to be ducking and dodging. All of these guys driving for us, we know each one is going to be going after [the 2013 title.]"

"It sounds like Kyle and Denny are already tied for the championship this year, but I'm looking forward to this anyway!" smiled Kenseth as his new team mates traded quips at this week's media event hosted by Charlotte Motor Speedway in Concord, North Carolina. Slightly more seriously, he added: "I feel like it's a great opportunity to go and hopefully compete for some wins and try to compete for a championship."

News of Busch's contract extension means that the biggest free agents still in play at the end of 2013 are 2004 Cup champion Kurt Busch, Earnhardt Ganassi Racing's Juan Montoya and Stewart-Haas Racing's Ryan Newman.

Kevin Harvick is also in the last year of his contract with Richard Childress Racing, and the team owner confirmed earlier this week that Harvick was leaving RCR at the end of 2013, but Harvick is understood to have a signed deal to move to Stewart-Haas from next year.