On lap 319, Danica hit Brad Keselowski from behind, causing the two of them to wreck.  But it turns out it was Danica's boyfriend, Ricky Stenhouse Jr, who forced Danica into Keselowski.

After making several pit stops to correct damage to her front end, Danica ended up finishing 29th.  Keselowski finished 36th.  Stenhouse finished 14th.

Keselowski initially took the blame, thinking he'd cut Danica off.  He even apologized.  But it was pretty obvious that Stenhouse was to blame.

Danica hasn't commented, but it sounds like she knew immediately her boyfriend blew the race for her, and she wasn't happy about it.  ESPN says, quote, "The tone in Patrick's voice over the radio and replay indicated Stenhouse played a role."

Danica and Ricky have been openly dating since Danica split from her husband.