Did a radio conversation between crew chief Chad Knaus and driver Jimmie Johnson get under Tony Stewart's skin? Credit: Autostock

Chase becoming a psychological battle?

HAMPTON, Ga. -- Both say there isn't a rivalry on the track. On paper, it's a flat-out war of words.

Tony Stewart and Jimmie Johnson fired shots at each other on Friday at Atlanta Motor Speedway, five days after their spirited short-track battle at Martinsville resulted in Stewart regaining the points lead.

Tony Stewart still leads the standings by 15 points over Jimmie Johnson. Credit: Autostock

Stewart bumped Johnson with 10 laps to go in the event last weekend at Martinsville, adding some much-needed drama between two dominant cars in this year's Chase for the Nextel Cup.

Stewart says that Chad Knaus, Johnson's crew chief, was attempting to play mind games by making remarks about Stewart's car during practice at Martinsville.

Stewart's team was listening to Johnson's frequency, and while Stewart refuses to reveal what was actually said, the issue was still being talked about as teams prepared for this weekend's MBNA Bass Pro Shops 500.

"I'm not going to quote [Knaus]," said Stewart. "But if you had a team and he was talking about you the way he talked about us, it was done with the intent of intimidating us."

Johnson disagreed.

"For somebody who says it doesn't bother him, evidently it has. Indirectly, I guess, something's gotten to him," Johnson said. "That's his deal and he's spending some time thinking about it.

"Last week, the reason we went out to follow him in practice was out of respect for him. He had the best car and we wanted to see how we stood up next to him.

"And we passed him. It felt good on the radio and we talked about it. So if he's still upset over that, then indirectly I guess we've gotten inside of his head even though he's said we haven't."

As the Nextel Cup Series hits Atlanta's 1.5-mile track, much of the championship focus has shifted to Johnson and Stewart, who have combined to win nine of the first 23 races.

Top GunsStewart jokes around with Dave Marcis and Rusty Wallace Too closeJohnson lines up right behind Stewart for Sunday's race Sign up for TrackPass now BUY YOUR NEXTEL DRIVER PHONE

The pair are the only two drivers to score 20 top-10s or more. Johnson is only 15 points back of Stewart in the championship hunt. Ryan Newman is third, 63 back.

Johnson warned against writing off the Roush Racing cars at Atlanta, where Roush dominated in the spring.

"Everybody is making such a rivalry out of the No. 20 and us. There are a lot of other good cars," Johnson said. "We're here at Atlanta and the Roush cars are here at the top of the board."

Stewart agreed that talk of an intense rivalry with Johnson is premature, but the events of Martinsville are still on his mind.

"You ask why it's such a big deal? It would be like somebody talking about your mom. It's something you don't like," said Stewart.