Alexander Gustafsson’s recent withdrawal from a November 19th UFC Fight Night main event vs. Antonio Rogerio Nogueira was the result of a back injury. The two-time LHW title challenger has fought just once this year, defeating Jan Blachowicz in September, and the Lil’ Nog fight represented a chance for a quick turnaround before the calendar turned to 2017.

Gustafsson’s co-manager, Tomas Ghassemi, told ESPN’s Brett Okamoto that Gustafsson has had a lingering back problem for "three to four years," and there’s no official diagnosis of what has been ailing the Swede.

"Pain will come up and then disappear whenever it wants," Ghassemi said. "It's maybe an issue with a disk. When the pain starts to go into his legs, that's when he knows it will affect his training and that's what happened with this one.

"We wanted a quick turnaround after this last fight. He's in great shape, but when it flared up and went into his legs, we couldn't take the fight. If you try to fight through it and lose, you can't blame it after the fact. It's better to deal with it now."

Ghassemi also noted that Gustafsson had dealt with back pain prior to his knockout loss to Anthony Johnson, but that Gustafsson “was lucky enough to have it mostly dissipate prior to the event.”

Gustafsson (17-4) is #2 in the UFC’s official light heavyweight rankings, and has been among the top fighters in the division for several years. His title fight losses to Jon Jones and Daniel Cormier were close decisions that could’ve gone either way. Those defeats, coupled with the KO loss to Rumble, have put the 29-year-old in a run where he’s just 2-3 in his last 5.

With Gustafsson withdrawing from the Nogueira fight, he’s since been replaced by Ryan Bader, in what will be a five-round showdown in Sao Paulo, Brazil.