Although they may seem to get along these days, Greg Biffle and Kevin Harvick have never quite seen eye to eye.
This feud goes back to the Nationwide Series in 2001, when Biffle was a rookie and Harvick was chasing his first series championship.
That May at Loudon, N.H., Harvick looked to be on the way to victory when the lapped Ford of Biffle held him up, handing the win to Jason Keller. Harvick met Biffle on pit road, where the two engaged in a shouting match before being separated by NASCAR officials.
The feud got interesting at Bristol in March 2002, when Harvick was wrecked by Biffle in the late going. Harvick promised payback and he kept his promise by famously leaping over Biffle's car in an attempt at strangling the Roush driver.
After that incident, the exchanges have been more tame, if anything. During a Nationwide race at Chicago in 2005, Harvick held up Biffle in an attempt to keep him a lap down. Biffle went on to finish second while Harvick won the race.
In theor latest incident, the two exchanged paint and words during practice at Martinsville in October 2011. No fists were thrown, but both ran into each other on the track and in the garage, and both teams almost came to blows.
Still, it would have been interesting if the two continued their rivalry to this day.