Alex de Minaur still plans to play doubles at the Paris Olympics.
Mirra Andreeva, 17, is the youngest WTA champion since Coco Gauff won 2021 Parma.
One Magdalena stood supremen in the first WTA all-Polish final.
"I'm sure Rafa will be in tomorrow's doubles because he trained well today," Spanish captain David Ferrer said.
The American started with Witt about a week and a half ago.
The Poles pushed past a pair of Czechs on Thursday in Prague.
"I'm happy I get to do this one more time," Andy Murray said of his Olympic farewell.
