Gonzalo Higuain threatened to quit football if Napoli failed to beat Dnipro in the Europa League, according to defender Artem Fedetskiy.
A solitary goal from Yevhen Seleznyov gave the Ukraine side a 1-0 win in the semi-final second leg and booked a place in their first ever European final with a 2-1 aggregate triumph.
Higuain was defended by head coach Rafa Benitez following a poor display on Thursday but Fedetskiy says the Argentine should now stand by his alleged comments.
"Before the match, Higuain said that, if Napoli didn't win, he would stop playing football," he told reporters.
"Now I'll wait until tomorrow. Everyone should take responsibility for the things they say. Maybe he didn't believe we were a worthwhile team."
Fedetskiy dedicated the victory to Ukraine's fighting forces, with the country still locked in a military dispute with Russia.
"I dreamed of this final. I'm happy and proud for my city, my team, my country. This victory is for our soldiers, who are defending us. They are our heroes," said the 30-year-old.