You know baseball season has begun when fans start throwing things at each other.
The Los Angeles Dodgers and San Diego Padres opened the 2016 MLB season at Petco Park on Monday afternoon, and it didn't take long for the longtime rivalry to raise its head.
As the Dodgers blew the game open with five runs in the sixth inning, some euphoric fans started chanting "Let's Go Dodgers!" in front of the home-town crowd.
ESPN, who was broadcasting the game live, cut to a pair of fans watching the game on the roof of the historic Western Metal Supply Co. building in left field and the cameras caught a Padres fan throwing peanuts at the happy Dodgers fans who were clapping in excitement.
Check out the video of the incident below.