For someone who retired in 2005, Mark Martin sure doesn't know how to quit. The 50-year-old Arkansas-native is taking his final shot at the NASCAR Sprint Cup Series championship. Arguably the best driver to have never won a championship, Martin has joined Hendrick Motorsports to run the full season in 2009.

"I could sit on the couch or I could drive this No. 5 car," Martin explained Wednesday. "There's nothing else in the world I'd rather do than to be behind the wheel of this No. 5 car and doing this. I know that there is nothing else out there that will take the place of racing a great race car and working with a great race team. That time for me is limited and I'm so grateful to have the opportunity to do this at this stage."

After announcing his intentions to retire from NASCAR competition at the end of the 2005 season, Martin reluctantly agreed to return to Roush Racing the following year. Since 2006, Martin has competed in 84 Cup Series events, scoring no wins, 16 top-5s and 37 top-10s.

"Around 2001, it started to gradually taper off," Martin said of his career. "You have to be happy. I wasn't that. I wasn't as happy as I should have been given all the circumstances. I had a great job, a great career. Loved Jack Roush like a brother. I just needed a break to catch my breath, and figure out what was important to me. I got that for two years and I had the time of my life. It was the best year of my life."

In 2007, Martin left Roush Racing after spending nineteen years with car owner Jack Roush. Martin joined Ginn Racing, running only a partial schedule.  When Bobby Ginn decided he couldn't take NASCAR any longer, Martin joined Dale Earnhardt Inc. as part of that merger. Uncertainty at DEI and an opportunity too good to pass up led Martin to Hendrick Motorsports.

"It's just unbelievable for me to get this chance," Martin added. "I know what I want to do. I was a little apprehensive about driving the full schedule, but I darn sure knew I wanted to drive that No. 5 car. This was what it took to make it work and I'm thrilled. This is what I want to be doing."

The addition of Mark Martin has made an already stellar organization that much more formidable. Joining teammates Jeff Gordon, Dale Earnhardt Jr. and defending champion Jimmie Johnson, Martin has made the Hendrick Motorsports team dangerous on all fronts.

"Mark is one hot commodity, even at 50 years old," four-time Cup Series champion Jeff Gordon pointed out. "He's extremely talented, very committed, and very capable of winning races and a championship. When you look at a guy like that as somebody who is available and that is interested, you are going to go after them very hard. It's going to take a good negotiator and there's nobody better at that than Rick [Hendrick]."

"The amount of respect that everybody in the series has for him is really the one thing that sticks out about Mark," Earnhardt Jr. added. "Everybody likes Mark and everybody thinks a lot of him. To me he is a role model in that aspect. In that respect he is a role model in that guys should try to achieve and gain that kind of respect from their peers like he has. I am glad he is here. He is an awesome race car driver. He's going to be fast and he's going to be hard to beat, but he's going to bring a lot to the table too. Just like being able to work closely with Jeff [Gordon] and Jimmie [Johnson] last year was exciting, it's going to be exciting to work with Mark on a teammate basis. I am looking forward to that."

One thing is certain; Mark Martin doesn't know how to slow down. The veteran driver has proven he still has what it takes to get the job done and has the endurance and strength to run with the best of them. Couple that with the top-notch equipment provided by Hendrick Motorsports and there is little doubt this 50-year-old has seen the last of his success.