It appeared Matt Kenseth was on his way to becoming the fourth driver to win back-to-back Daytona 500s. However, while leading with 52 laps to go, smoke began erupting from underneath Kenseth's No. 20 Toyota and he immediately slowed on the track and came down pit road.
According to Kenseth, the issue had something to do with either the transmission or the engine, but he was unsure what exactly ended his race prematurely.
Kenseth had led a race-high 86 laps before heading to the garage.
And just minutes after mechanical gremlins sidelined Kenseth, his teammate Kyle Busch also experienced problems, as he too started smoking with what appeared to be a blown engine. Like Kenseth, Busch went to the garage.
Just prior to Kenseth and Busch's issues, Joe Gibbs Racing had been running first, second and third.
The third JGR entry, driven by Denny Hamlin, has inherited the lead with green flag pit stops approaching. Martin Truex Jr., Greg Biffle, Jimmie Johnson and Jeff Gordon make up the rest of the top five.
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