According to Fiveouncesofpain, Frank Mir has pulled out of his UFC 98 Heavyweight title unification fight with Brock Lesnar because he recently had his knee scoped and will be unable to train for 4-6 weeks.
Apparently Mir's camp asked the UFC not to announce that the fight was taking place at UFC 98 but the UFC ignored the request. Dana White still seems to think Mir will be fighting in May but Mir would probably like to train for the five round championship fight.
The fight was scheduled to be the headliner for the May 23rd pay-per-view event.
UFC 98 will also feature the greatly postponed grudge match between Matt Hughes and Matt Serra which is hardly a big enough fight to carry the card.