This kiddie baseball coach has a vengeful streak.

Long Island resident Robert Sanfilippo, 45, was arrested Friday for allegedly stalking and harassing a rival coach, Suffolk County cops said.

Sanfilippo bought an untraceable phone and used it to send harassing text messages and pictures to the other coach, threatening the man’s wife and 10-year-old son, police said.

The Huntington resident, who coaches the Long Island Vengeance youth team, got into an altercation with the victim in May. Sanfilippo was arrested and hit with 20 counts of aggravated harassment and one count of stalking.