McMurray turned a lap of 96.509 mph in his Chevrolet to earn the top starting spot for Sunday's race. He came to Martinsville ranked 28th in the Sprint Cup Series standings and with a season-best finish of 18th in the opener at Daytona.
"This is really big for our team," said McMurray. "We've had some really good cars, and for the most part, the short tracks is where we've run the best. But we got caught up in that wreck at Phoenix and at Bristol ... got caught up in a wreck. It just seems like we've had really bad luck. But I hope this turns around for us."
McMurray said he was pacing through his team hauler during the qualifying session, and his Earnhardt Ganassi Racing crew was making fun of him for being so nervous about potentially winning the pole.
"I told them, 'Martinsville, the pole, if you get the No. 1 pit stall here, it's huge. I think that can win the race for you,' " McMurray said of the stall he'll use Sunday at the exit of pit road.
Ryan Newman qualified second with a lap of 96.342 in a Chevrolet. Kasey Kahne qualified third in a Toyota and was followed by Joe Gibbs Racing teammates Joey Logano and three-time defending race winner Denny Hamlin.
Five-time Martinsville winner Jimmie Johnson qualified 17th.
But qualifying results were overshadowed by tire troubles for the second time in three races.
The tires Goodyear brought to Martinsville are leaving marbles made of rubber all over the track. It's a different tire than the one used last year because Goodyear wanted to prevent grating on the left-side tires that often occurs when cars slide from the asphalt racing surface into the concrete corners.
Because of the marbles and the lack of rubber accumulating on the track surface, drivers spent much of Saturday complaining about a lack of grip.
"The tire is really crappy," said Dale Earnhardt Jr., "but that's just the way it is. There's not much they can do about it."
NASCAR Sprint Cup Series director John Darby said drivers had to adjust the different "drivability characteristics" of the tires.
"The tire is not failing," Darby said.
Kyle Busch said his tires were wearing out faster, and grip was an issue. Earnhardt said he could only go about 12 laps before performance was affected by the tires.
"They don't drive real good after 12 laps; they get real, real loose," he said. "(The teams) are just hoping that the track will do what it normally does and that will mean the track will come to our setup. Hopefully that happens. You've just got to take that gamble."
Drivers said the Martinsville tire problem isn't even close to what occurred two weeks ago at Bristol, where Goodyear had to overnight new tires to the track because the ones being used suffered excessive wear.
"This is not at all an issue like we had at Bristol," Jeff Gordon said. "That was extreme and they made a good decision to come in and change that tire."