SECAUCUS, N.J. — Bob Costas has left HBO and joined the new MLB Network.

The agreement announced Tuesday does not affect Costas' relationship with NBC, where he has worked since 1980. Although NBC doesn't televise major league games, it does report on them on its news program and those of its affiliates.

"No, we don't have a problem," NBC spokesman Brian Walker said.

Costas hosted the MLB Network's first show on Jan. 1. HBO insisted on cable exclusivity.

"Bob Costas was a terrific addition when he joined HBO Sports eight years ago, providing us with a distinct and unique presence," HBO Sports president Ross Greenburg said. "Television is about change, and we respect Bob's decision to move to the MLB Network."