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]
(..) ln light of the dark events of recent weeks. . . . . .Professor Dumbledore has granted me permission to start this Dueling Club. . . . . .to train you all up in case you ever need to defend yourselves. . . . . .as l myself have done on countless occasions. For full details, see my published works. (..)2002 Harry Potter and the Chamber of Secrets