According to a report by, current interim UFC Heavyweight Champion Frank Mir has suffered a back injury that has kept him from training recently and will force him to pull out of his scheduled unification fight with current UFC Heavyweight Champion and former WWE star Brock Lesnar at UFC 98 on May 23. There are also other sources claiming that Mir was having issues with his knee and had surgery recently that will keep him out of action for the next next four to six weeks to heal. It remains to be seen what the company will be doing for UFC 98 and if they will find a replacement for Mir or simply scrap the fight all together.