The bout was originally scheduled for UFC 98, but was moved after Mir suffered a knee injury during training. Greg Nelson, the head trainer of Brock Lesnar at the Minnesota Martial Arts Academy, told Rod Moyer of FightLine.com that Lesnar used the extra time to get more training in.

"The more time we get to train is always going to be a benefit to us," Nelson explained. "He’s [Brock] always anxious to get into the octagon and mixing it up, but we basically started our training camp for the Mir camp just like were in a fight on May 23, and took advantage of it. We brought everyone in we were going to bring in anyways. We got an extra training session in [before the current 8 week training camp]."

Nelson also explained that Lesnar has been doing well against the heavyweight jiu-jitsu fighters that they have brought in.

"We bring in a variety of jiu-jitsu guys that are heavyweights, and he’s been doing very, very well against them on the ground so, you know, his ability to learn and basically adapt to the game is really remarkable and very fast paced," Nelson stated. "When he see’s something, he’s learns it, and then he learns a counter to it and he just keeps on rolling so he’s very fast."

Lesnar and Mir are no strangers to each other, as Mir defeated Lesnar in Lesnar's UFC debut at UFC 81: Breaking Point. Lesnar had secured an early takedown and landed a flurry of strikes on Mir, but was deducted a point for hitting Mir on the back of the head, which caused a break in the action. When the fight resumed, Lesnar managed to secure another takedown, but Mir managed to secure a kneebar and force a submission at 1:30 of the first round. Nelson noted that Lesnar will be a lot more prepared for Mir this time around.

"He’s so athletic that it’s easy for him to learn stuff, unlike the first fight, you know, his first fight he was a bit maybe too fast paced, a little too hyper-charged, that got him in a little bit of trouble," Nelson continued. "So this time he’s been in there, slowing down a little bit. He’s got heavier hands, better boxing, better jiu-jitsu, and wrestling’s going to obviously be his strong point."

Nelson also stated that he expects the fight to be similar to the first fight.