The team is looking to 'defend' its national title. [=to win the national title again]
As a U.S. senator, it is my responsibility to 'defend' [='uphold'] the Constitution.
She successfully 'defended' her championship. [=she won the championship again]
(..) my model of manhood, and my estimation of him will govern the prospects of my adult relationships. So I hope you bear in mind that any knock at him is a knock at me, and I'm far too young to defend myself against such onslaughts. Mm-hmm. Go watch your cartoon show, dear. Come on, Bart. (..)1989 TvShow: The Simpsons Title: Simpsons Roasting on an Open Fire Season: 1 Episode 1