The San Francisco 49ers signed tight end George Kittle to a four-year, $76.4 million contract extension, a source familiar with the agreement told UPI on Tuesday.

NFL Network's Ian Rapoport reported on Tuesday that Kittle and the 49ers agreed to terms on a four-year, $76.4 million extension that will make him the league's highest-paid tight end. The 49ers entered the day with $39.4 million in cap space, not accounting for any potential changes to Kittle's cap number with his new contract.