TALLADEGA, Ala. -- Contracts, commitments and collateral steered Mark Martin away from Roush Racing to MB2 Motorsports for next season.

Martin, competing for the Nextel Cup title, announced Friday that he will leave Roush after 19 seasons. Martin will run 20 points races and the two all-star races for MB2 Motorsports. He'll share the U.S. Army Chevrolet with newcomer Regan Smith, who will drive the remaining 16 races. Joe Nemechek moves to an as-yet sponsored No. 13 car.

Dan Davis, director of Ford Racing Technology, said he was "disappointed'' that Martin leaves Ford.

Martin, who won all 35 of his Cup races with Roush, said he signed a five-year contract that includes flexible options, allowing him to alter his schedule however he wants.

Roush Racing couldn't match that deal because it didn't have an available team. Roush said that a contract with sponsor AAA called for the No. 6 team to have a rookie driver next season.

NASCAR's limits on how many teams an organization can have meant Roush couldn't offer Martin a Cup ride. Roush offered a full time truck ride. Martin liked that idea until MB2 Motorsports approached him a couple of weeks ago with the part-time Cup schedule that gives Martin the time off he craves. Martin says the first race he'll likely miss next season will be at Bristol or Martinsville next spring.

The move might seem odd because Martin leaves a title-contending team for a team that doesn't have a driver in the top 30 in points. Sterling Marlin and Nemechek have combined for one top-10 finish this season.

Team changes

The Wood Brothers have signed Kelly Bires as a development driver, co-owner Eddie Wood said. Bires, 22, drove in Friday's ARCA race. He's from Mauston, Wis.

Also, Wood said a couple more sponsorship deals are close to being set that will define how many races Ken Schrader and Jon Wood will drive next season. They'll share the No. 21 car. Wood is expected to drive in 10-12 Cup races next season.

Pit stops

Car owner Jack Roush says that "we're in discussions'' with Jacques Villeneuve, a Formula One champion, about driving for the team. ... Mark Martin won the pole for today's Craftsman Truck race at Talladega.