The Mariners and pitcher Felix Hernandez have finalized their five-year, $78 million deal. The contract will keep Hernandez in Seattle through the 2014 season. He said personal growth allowed him to grow as a player last season. "It's the maturity, man. I had my kids and it made me grow up," Hernandez, 23, said Thursday. He went 19-5 with a 2.49 ERA in 34 starts in 2009.