CHULA VISTA (CNS) - A field hockey coach who carried on a yearlong sexual relationship with a South Bay teenage girl was sentenced Monday to a two-year jail term and ordered to register as sex offender for life.

Jose Antonio Carrillo, 50, pleaded guilty in October to eight charges, including sexual intercourse with a minor.

Carrillo, a volunteer coach at Bonita Vista High School and an hourly instructor at Jackie Robinson YMCA in San Diego, carried on the sexual relationship with the girl for a year beginning in July 2010, said Deputy District Attorney Mary Loeb.

Carrillo was arrested July 6 during a field hockey event in Chula Vista.

The case came to light that week when the 16-year-old victim's aunt saw the girl with an unfamiliar cell phone and asked where it came from, according to Chula Vista police Capt. Gary Wedge.

The teen said Carrillo had given it to her, then admitted to the affair with the coach under further questioning, the captain said.