Anyone who has attended recent Sam's Town 300s at Las Vegas Motor Speedway knows one thing: never leave until the checkered flag waves.  Last year, Jeff Burton won as Kyle Busch spun. This year, Mark Martin inadvertently provided the fireworks.

Martin was involved in an accident that included former teammate Carl Edwards and JR Motorsports stable mate Brad Keselowski on lap 197 of the 200-lap race.  Martin found himself in sixth place after a final round of pit stops with just 10 laps remaining.  He chased down frontrunners Keselowski and Edwards, who were racing side-by-side.  Martin made contact with Edwards' car, which caused him to slide into Keselowski.  As the pair wrecked, Martin motored past and gained the lead.

"I've got to apologize before we do anything else," said Martin, who long ago earned a reputation as one of the sport's cleanest drivers.  "I ran into the back of Carl and I hate it. I just hate it, really, because we (JR Motorsports) could have had a one-two finish. I hate that it happened, but I sure didn't intend for it to happen."

"I'd like to be really mad at Mark," said Edwards, who wound up 14th, "but I'm sure he made a mistake.  He's a heck of a guy and he has a lot of respect."

"I felt like I had a chance to win or finish in the top five," said Keselowski.  "I'm not sure what happened at the end." 

"I'm really happy.  It's funny how things work out, to have Mark drive a car out of our shop," said team owner Dale Earnhardt Jr. "I've known Mark forever and he taught me a lot. We were proud of both teams, they were running pretty good and Mark had a real strong car all day. We all know he's one of the cleanest drivers out there. He's taught this entire garage how to drive clean and act respectfully."

Earnhardt Jr. was asked about Keselowski, who eventually was scored in 23rd position.

"He's a good kid and he'll be stronger because of what happened today. We'll put it behind us. It's hard to stomach but we'll be stronger the next race. He knows the type of driver Mark is and it's awesome to hear Mark be honest about the situation."

"The car was real good -- really good at staying on the bottom," said Martin.  "We probably weren't the fastest car here today but we were real solid and real steady.  We made good adjustments on the car and the race track was awesome. It really means a lot to me to drive the 5 car. Rick (Hendrick) let me drive it three times last year and we came up with two second-place finishes.  With Dale (Earnhardt) Jr. - to be a part of JR Motorsports is something really special to me.  Junior and I have known each other since he was about three-and-a-half feet tall.  It's pretty cool.  This is a real special day for me and I really appreciate the opportunity they gave me to race in cars that can contend to win."

Martin's victory was the 48th NASCAR Nationwide Series win of his career and he earned $94,045.

Greg Biffle finished second and Clint Bowyer was third.

A race-record number of caution periods - 13 - slowed the race for 55 laps.

Dario Franchitti, who finished sixth, won the Raybestos Rookie of the Race Award.