NASCAR drivers Tony Stewart and Kurt Busch have been smacked with probation, and will be monitored closely during the first six races of the Sprint Cup season. The penalty was levied as a result of last week's incident of on-track road rage during practice, where Busch repeatedly rammed the side of Stewart's No. 20 Chevrolet on the way to the pits in retaliation for being rear-ended. In what was supposed to be a cool-down meeting with NASCAR officials immediately following the altercation, Stewart allegedly threw a punch at Busch in response to the latter's insults. Both drivers are notoriously hot-tempered, and their embattled history goes back to at least last year's Daytona 500, where Busch wrecked Stewart and put both cars out of the race. During a separate incident last season, Busch slammed his car into Stewart's pit area for a shouting match, nearly running down members of Stewart's pit crew. Now both drivers have been ordered to steer clear of each other?and despite the put-it-behind-us rhetoric that their respective PR machines have been delivering, it's clear that these two hot-heads will be beginning the '08 season with a pretty deeply entrenched feud.