Stewart-Haas Racing revealed on Monday that Tony Stewart will miss the remainder of the 2013 Sprint Cup Series season and Mark Martin will substitute for him in the No. 14 Chevrolet.

Stewart, a three-time Sprint Cup champion, has missed the last two races after he sustained a broken right tibia and fibula in an accident during a sprint car race on Aug. 5 at Southern Iowa Speedway in Oskaloosa, Iowa. He underwent two surgeries to repair his fractured leg. SHR expects Stewart to resume his driving duties in time for pre-season testing in January 2014.

Martin has been granted an early release from Michael Waltrip Racing. He was scheduled to drive the No. 55 Toyota for MWR in 10 of the remaining 13 Sprint Cup races this season. Martin's first event with SHR will be on Saturday night at Bristol Motor Speedway.

Austin Dillon drove the No. 14 car to a 14th-place finish in Sunday's race at Michigan International Speedway. Martin was behind the wheel of the No. 55 for the final time in that event. He originally had planned on departing MWR at the end of this season. Martin held the lead late in the race but ran out of fuel with less than four laps to go, allowing Joey Logano to take the top spot and then grab the win.

"After consulting with Tony's doctors and speaking with Tony, we agreed it was best for him to focus on his recovery," SHR competition director Greg Zipadelli said in a statement. "For the No. 14 team, our focus is on positioning them for a run at the owner championship. Mark Martin and Austin Dillon give us the best opportunity to do that, and we certainly appreciate Michael Waltrip Racing and Richard Childress Racing for making Mark and Austin available to us."

Prior to his injury, Stewart sat 11th in the point standings and held the second and final wild card spot. This will be the second year that Stewart is not in the Chase. He did not make it into the playoffs in 2006, the year after he won his second series title.

"Obviously, I'm disappointed to be out of the Bass Pro Shops/Mobil 1 Chevy for so long, but the team is in very good hands with Mark Martin and Austin Dillon," Stewart said. "Mark is someone I've looked up to my entire career, and I have a tremendous amount of respect for him. Austin is a great young talent, and he showed that Sunday at Michigan. Greg Zipadelli, Steve Addington (crew chief) and everybody at SHR supports them 100 percent. This isn't a situation anyone wanted, but we're going to make the best of it. In the meantime, my focus is on getting healthy and getting back into my Bass Pro Shops/Mobil 1 Chevy."

Martin has 40 career wins in NASCAR's top series, but he has not been to victory lane since September 2009 at New Hampshire, driving for Hendrick Motorsports at the time. He also has scored 271 top-five finishes, 462 top-10s and 56 poles in 870 starts. The 54-year-old Martin had been driving a partial schedule for MWR since the start of the 2012 season.

"I'm proud of the work we've done the last two seasons, and I'm extremely thankful for the effort everyone on my team and at MWR put behind me," Martin said. "I also want to thank Michael Waltrip and (co-owner) Rob Kauffman for giving me this opportunity. They are building a strong organization at MWR and one that's going to be a force in NASCAR for years to come both on and off the track."

Brian Vickers will drive the No. 55 in all but one of the last 13 events this season. Waltrip is scheduled to drive the car in the Oct. 20 race at Talladega Superspeedway. Vickers is presently a full-time competitor in Nationwide for Joe Gibbs Racing. He was originally scheduled to drive in three more Sprint Cup races this year.

Last week, MWR announced that Vickers will drive the No. 55 full-time in Sprint Cup next year, with Aaron's sponsoring his efforts in all 36 races.