CONCORD, N.C. — NASCAR received favorable driver reviews about the switch from a wing to the traditional spoiler.

NASCAR opened a rare two-day test session Tuesday at Charlotte Motor Speedway for teams to get their first extended track time with the spoiler, which will return to competition for the first time since 2007 at this weekend's race at Martinsville Speedway.

"It was a very important day for us, and I felt like it went really well," said four-time series champion Jeff Gordon. "I liked the way the cars looked with the spoiler, and the cars drove really well. All in all, it was a great day for us and we certainly gathered a lot of data."

The rear wing was a component of NASCAR's current model of race car that was phased into competition in 2007. Fans disliked the look of it, and drivers listed it among their dislikes of the car.

"We had reasons to go to the wing. Some of those might not have panned out, " said Robin Pemberton, NASCAR's vice president for competition. NASCAR decided during the offseason to go back to the spoiler, partly in a hope that it improves competition. Martinsville, the sixth race of the season, was the earliest the change could be made because of all the planning involved in such a technical change to a race car.

Dale Earnhardt Jr. believes switching back to the spoiler, which was last used in the 2007 finale at Homestead, will be beneficial to most drivers because they have vast experience with it.

"The spoiler always worked pretty well and did a pretty good job, and they've got a lot of information from the spoiler over the years," he said. "So we all kind of know how the spoiler works."