MARTINSVILLE, Va. -- When he first suffered a torn anterior cruciate ligament to his left knee while playing pickup basketball on Jan. 22, Denny Hamlin tried to downplay its significance.

He insisted -- again and again -- that he could make it through the 2010 Sprint Cup season as driver of the No. 11 Toyota for Joe Gibbs Racing without missing a beat. Surgery could wait until after the season, he repeatedly said.

Well, Hamlin changed his tune this weekend at Martinsville Speedway, where it was announced that he will race in this Sunday's Goody's Fast Pain Relief 500 and then undergo surgery to repair the torn ACL "as soon as I can early Monday morning." If Sunday's race gets rained out -- a distinct possibility since local forecasts are calling for an 80 percent chance of rain most of the day -- Hamlin said he still will participate in the race and move the surgery to Tuesday.

"We were going to wait until the end of the season, but just decided that it wasn't a good idea," said Hamlin, a preseason favorite to challenge for the championship who is off to a slow start and sits 19th in points. "We were doing some further damage to the knee and to me it's not something that's worth suffering forever or having a permanent limp or anything like that. It just didn't make much sense."

The surgery will be performed by Dr. Patrick Connor with OrthoCarolina in Charlotte, N.C. Hamlin said that he hopes to be back in the car for the very next Sprint Cup race on April 10 in Phoenix, but Hamlin said that team officials have arranged to have Casey Mears standing by as an emergency fill-in -- either for the entire weekend, or if Hamlin starts the race but needs to climb out of the car at any point.

Mears, who finished 21st in points in 2009 while driving for Richard Childress Racing, has been attempting to run Cup races in the No. 90 Chevrolet fielded by Keyed-Up Motorsports. The car failed to qualify for four of the first five races, with Mears finishing 30th in his 2010 debut last Sunday at Bristol.

"We're going to have Casey Mears standing by for a few weeks just to see how things go," Hamlin said. "Obviously, they've been trying to get that program together and we felt like he was our best option as far as being able to use someone to get a good finish."

Hamlin said he has been told by his physician that no one can be certain about how his recovery from the surgery will go.

"From what the doctor told me and that's really all I can go by, is that recovery for everyone is different," Hamlin said. "Some people take right to it; some people it takes a little bit longer. Everyone is different.

Kneeds to be done

Denny Hamlin talks about how surgery might affect his racing.

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"We're going to do the cadaver graft so it's going to be a false piece that they will add in there. It just depends on how your body handles it. Right now he says that I'll be able to get in the car at Phoenix -- there's no doubt that I'll be able to get in it. It's just tolerance of pain is what's going to be the limiting factor. I'm not going to do any further damage to it once [the surgery is] done. It's going to be strictly pain limited."

The touchy problem with that is Hamlin is not permitted to take any pain medication while he is driving a Sprint Cup car. But Hamlin said he should be used to that.

"Rehab starts right afterward. No, I haven't taken any medication," Hamlin said. "After I did it [in January], I hadn't taken anything for medication. Obviously, the on-track policy they have with the drug policy, you're not able to take anything. I didn't want to have anything that I was going to get used to, so I decided to not even go there in the first place.

"They said [rehab] starts two days after [the surgery]. We'll start working on getting the range of motion back and things like that. They said I'll be on crutches right up until Phoenix and then from there, we'll just kind of see where our range of motion is and things like that. As long as they can just pry me in that seat, they'll have a tough time prying me out."

While Hamlin admitted he has been in more pain than he has been letting on during the first five weeks this season, crew chief Mike Ford said Hamlin has kept it to himself.

"I don't talk to him about that. It's kind of out of sight, out of mind. In the car, he hasn't complained one ounce about it," Ford said. "But also, that's on him. It was of his own doing."

Obviously, Hamlin planned the surgery prior to a rare off week for the Sprint Cup Series. Hamlin also admitted that short-track racing, such as last week at Bristol and this weekend at Martinsville where a driver must get on and off the clutch and brakes more often than at bigger tracks, played a role in convincing him that he could put off the surgery no longer.

"When I did initially tear my ACL, the rest of my knee was completely fine; there was nothing else wrong with it," Hamlin said. "Now it seems like we've now cracked the meniscus [cartilage] and if that goes, then what will happen is the knee will completely lock up and then you have to get [the surgery] done. So it's best for me to limit my time out of the race car by doing it on an off week. Just take that week and take my lumps that first week and then get back in the car just as soon as I can.

"For me, it was more fearing long-term [damage] and if something further goes wrong. With not having [had it repaired earlier], there's nothing else around the knee to support it, so I've done further damage [since the initial injury]. I noticed that after the Bristol race it was as achy as it had been and hurt pretty good. The best thing is to just get it over with."

Related:
• January: Hamlin suffers tear of ACL in left knee
• February: Hamlin won't let knee faze him in car