Joliet, Ill. ? When Justin Labonte rumbled off on his victory lap, waving the checkered flag from his window, it was hard to tell who was prouder — father or son.

Labonte extended his family’s winning tradition to another generation Saturday, earning his first NASCAR Busch series victory at the Tropicana Twister 300 as his father Terry looked on.

“To me, personally, it was bigger than any win I’ve ever had,” said Terry Labonte, a two-time NASCAR Winston Cup champion. “I couldn’t even talk after the race. It’s pretty special, it really is. I don’t know what else to say.”

Running on Mike Wallace’s bumper for the last three laps, Justin Labonte said he didn’t think he could catch Wallace. But Wallace ran out of gas after they took the white flag for the final lap, and Justin Labonte flew by him and cruised to the win.

He beat Jason Keller by 0.419 seconds. Jeff Burton was third.

“I was going to do a burnout,” Justin Labonte said, “but I can remember my dad saying nobody should do a burnout.”

Terry Labonte always has been understated in his victory celebrations, getting the checkered flag and holding it out the window as he takes his victory lap. There also was the matter of the engine. Justin Labonte is running part-time on the Busch series this year, and he knew he couldn’t afford to blow out his best engine.

So while the rest of the field left the track, Justin Labonte drove to the flagstand and asked for the checkered flag. It dropped on the roof, and lay there for several seconds before Justin climbed halfway out of the car and grabbed it.

“He didn’t have the fastest car, but something good happened to a good person and a good family, and that’s pretty cool to see,” Burton said.