Fight Bravely
noun, する verb
If you're involved in a daring struggle you need to be strong and fight bravely. Even if you might get hurt, you should do your best!
かんとう
This is a jukugo word that uses the on'yomi readings of the kanji. You should be able to read this on your own.
優勝候補を相手に、よく敢闘したと思います。
I think I fought pretty bravely against a favorite for the championship.