LOUDON, N.H. ? Like many youngsters, Martin Truex Jr. fantasized about stepping up to the plate with two outs in the bottom of the ninth and the bases loaded.

He’ll be a pinch-hitter today, replacing Dale Earnhardt Jr. in the No. 8 car at some point during the first NASCAR Nextel Cup race of Truex’s career.

Recovering from a fiery crash last weekend, Earnhardt plans to drive only a handful of laps during the Siemen’s 300 before handing off to Truex, who will attempt to give his boss and friend a victory.

“That’s a big task,” Truex said. “But I don’t think it’s out of the question.”

Truex, 24, was supposed to make his first Cup ride on New Hampshire International Speedway’s flat, 1.058-mile oval in September, driving a car fielded by Earnhardt’s Chance 2 Motorsports, the team for which Truex drives in the Busch Series. Truex tested here this month because of that plan, having no idea that practice would become so vital so soon.

Earnhardt spent one night in the hospital and came away from his frightening crash with second-degree burns on his legs, neck and chin. His wounds and pain led the Dale Earnhardt Inc. team to enlist Truex to practice and qualify Earnhardt’s car Friday and stand by today as a relief driver.

Earnhardt will start the 300-lap, 317.4-mile race — the driver who starts the race earns the championship points — and Truex will relieve him at the first opportunity, perhaps the first caution period.

Earnhardt goes into the race second in the standings, 105 points behind leader Jimmie Johnson.