Sources: Paulo Costa battling the flu, April 17 bout with Robert Whittaker off

Paulo Costa is out of the April 17 main event fight against Robert Whittaker, sources told ESPN.

The news was first reported by MMAFighting.com.

According to sources, Costa is battling the flu, not COVID-19, and as a result had to withdraw from the fight. He's hoping the UFC will move it to their May 1 or May 8 Fight Night card, but no word just yet on what the promotion will do, sources say.

Costa (13-1) is coming off a loss to middleweight champion Israel Adesanya in September, while Whittaker (23-5) has won his past two fights.