Million Dollar Baby

Today's main clues are: Suffer a serious blow; Out, so to speak; Give up. A very straightforward puzzle with a theme prime with the clue 'Boxing venue'.

Since it comes up so often, I need to learn my 9 Muses:
Euterpe (music)
Calliope (epic poetry)
Clio (history)
Erato (lyric poetry)
Melpomene (tragedy)
Polyhymnia (sacred poetry)
Terpsichore (dancing)
Thalia (comedy)
Urania (astronomy)