Paulo Costa has withdrawn from his UFC Vegas 24 headlining bout opposite Robert Whittaker. Sources confirmed that Costa withdrew because of a severe bout of the flu, which has compromised his ability to train. AgFight initially reported that the bout was in doubt, but it now appears to be nixed. The UFC Vegas 24 fight card is currently slated for April 17 in Las Vegas. It should be noted, however, that UFC 261 also is approved for Las Vegas, though UFC president Dana White on Monday announced that the pay-per-view event would take place to a packed house of fans at VyStar Veterans Memorial Arena in Jacksonville, Fla.