UFC 160: Mike Pyle vs. Rick Story booked for May 25 with Gunnar Nelson hurt

Ultimate Fighting Championship (UFC) has been tinkering with its upcoming UFC 160: "Velasquez vs. Bigfoot 2" pay-per-view (PPV) fight card, today confirming a welterweight switcheroo between longtime veteran Mike Pyle and up-and-coming grappling phenom Gunnar Nelson, originally booked for May 25, 2013 at the MGM Grand Garden Arena in Las Vegas, Nevada.

Gunny blew out his knee and will be forced to undergo surgery.

Taking his place will be Rick Story (15-6), who is fresh off a UFC 158 drubbing of Quinn Mulhern. "The Horror" has struggled to find his footing in recent years, going just 3-3 inside the Octagon after an electric 6-1 start, but can get right back into "the mix" with another couple of wins.

Starting in "Sin City."

Pyle (24-8) is riding a three-fight winning streak that includes three finishes by way of knockout or technical knockout. The 37-year-old "Quicksand" was last seen beating the brakes off James Head at The Ultimate Fighter (TUF) 16 Finale back in December.

Can he beat the Story-ed veteran and get himself into the title chase?

UFC 160 will feature the second showdown between UFC Heavyweight Champion Cain Velasquez and 265-pound "Bigfoot" Antonio Silva. Former division kingpin Junior dos Santos will try to get back into the title picture against Mark Hunt while Glover Teixeira makes his case for a run at the 205-pound title opposite James Te Huna.

For all the UFC 160 news that's fit to print click here. To see the full fight card and line up for the Memorial Day Weekend event click here.