Since the final lap of last month's Sprint Cup race at Pocono when Jimmie Johnson and Kurt Busch slammed into each other as they raced for third position their temperatures seem to rise whenever they are near each other, on and off the track.

Kurt Busch went on to claim third at Pocono while Johnson ran fourth. Johnson confronted Busch on pit road after the race with the defending and former NASCAR champions exchanging words. Busch said Johnson was "real excited" when he approached him at Pocono. Johnson said later that Busch "just started running his mouth."

In an interview at Watkins Glen the following weekend Busch said, "I'm in his head, and if I'm in his head then he's got to worry about us running through this Chase."

Johnson countered "at the end of the day I'm not gonna let him run his mouth at me."

Busch and Johnson competed in the Nationwide race at Watkins Glen with Busch winning from the pole after pulling away from Johnson on the last restart with two laps remaining.

That was as close as they were during the weekend of road racing in upstate New York, Johnson finished 10th in Monday's rain delayed race with Kurt Busch sidelined in 38th.

Johnson finished second again the next week in Michigan, this time to Kyle Busch. The race went into overtime when Kurt Busch hit the wall and brought out the final caution of the day.

Fast forward to Richmond where the Johnson and Busch rivalry escalated to a new level during Saturday night’s Wonderful Pistachios 400.

Entering turn one on lap 186 of Saturday night's 400-lap race Kurt Busch sent Johnson for a hard meeting with the wall. Johnson retaliated on lap 246 by spinning the No. 22 Penske Dodge and himself resulting in both cars making contact with the wall.

"I got your number," Busch said over the radio.

Tension continued to fill the air after the race with Busch referring to Johnson as the "'Five-Time Chump'" before exchanging words with two reporters.

A NASCAR.com reporter, Joe Menzer, attempted to interview Kurt Busch after he climbed from his car on pit road. Busch interrupted Menzer and walked away then returned shouting expletives and acting as if he wanted to fight.

Busch was restrained by members of his Penske Racing team.

Busch then joined fellow Chase drivers for post-race interviews and was separated from Menzer by a NASCAR representative inside the media center after approaching the reporter a second time.

During the ensuing question and answer session AP reporter Jenna Fryer referred to the comment Busch made at Pocono that he had "gotten inside Johnson's head."

Busch immediately took offense saying, "I didn't say that tonight." Fryer produced the transcript containing the quote on Dodge Motorsports letterhead with Busch tearing the release and dumping it on the reporter’s computer as he left the room.

Busch did apologize to the two reporters on Monday and NASCAR does not plan any action other than "discussing" the matter with Busch this week.

Only time will tell if this ongoing feud between two championship contenders will continue to simmer and boil over affecting their chances and those of the other ten competitors in the Chase for the 2011 Sprint Cup.

Stay tuned.

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