Ariel Shnerer of The Fight Network is reporting that a rumored middleweight matchup for UFC Fight Night 15 in September between Thales Leites and Dean Lister has been postponed.

According to Shnerer, the bout is off the Sept. 17 fight card because of a knee injury sustained by Lister during training.

UFN 15 will emanate from Omaha Civic Center in Omaha, Nebraska and will feature a lightweight main event between Nate Diaz, the winner of the fifth season of “The Ultimate Fighter,” and Josh Neer.

The event will serve as a lead-in for the season premiere of the eighth season of “The Ultimate Fighter” and will also feature bouts between Houston Alexander vs. Eric Schafer, Clay Guida vs. Mac Danzig, Joe Lauzon vs. Kyle Bradley, Alan Belcher vs. Ed Herman, Jeremy Horn vs. Wilson Gouveia, and Drew McFedries vs. Mike Massenzio.

A lightweight battle between castmates from the fifth season of “The Ultimate Fighter” is the latest bout added to UFC 87, scheduled to take place on August 9 at the Target Center in Minneapolis, MN. It was be Manny Gamburyan, the runner-up from TUF 5, taking on Rob Emerson.

The news was first reported on Monday by our friends at MMAjunkie.com.

Since losing the TUF 5 final against Nate Diaz due to a shoulder injury, Gamburyan has gone 2-0 in the UFC with submission wins over Nate Mohr at UFC 79 and Jeff Cox at UFC Fight Night 13.

Emerson, who is 7-6 according to Sherdog’s fight finder, last competed at UFC 81 in February, where he recorded a split decision victory over Keita Nakamura. He had been scheduled to fight this past weekend vs. Terry Etim at UFC 84 as an injury replacement, but he ended up having to be replaced himself by Rich Clementi due to injury.

UFC 87 is scheduled to be headlined by a welterweight title defense by Georges St. Pierre against number one contender Jon Fitch. Other bouts include a heavyweight tilt between Heath Herring and Brock Lesnar as well as a lightweight bout between Kenny Florian and Roger Huerta.

UFC.com has listed on its event page for UFC 84: Ill Will that TUF 5’s Rob Emerson will take on Terry Etim at the event.

This listing goes against a widely accepted report from MMA Junkie back in February that Etim would take on Jeremy Stephens. In my recent MMA blog travels I haven’t noticed anyone disputing Junkie’s report or mentioning a possible injury to Stephens that would have kept him out of the bout.

It must be noted that UFC.com never officially announced Etim vs. Stephens. It just seems strange to me that Stephens would announce that he has signed a bout agreement to fight Etim but then for the fight to fizzle out without anyone really noticing. Whatever the reason, it will most likely come out in the next few days.

Stephens’ “replacement”, Rob Emerson (7-6) is coming off a split decision victory over Keita Nakamura at UFC 81 back in February.

Update: MMA Junkie has now confirmed that Stephens had to pull out of the bout with Etim due to a “minor legal situation.”

Read more UFC 84 content on FiveOuncesOfPain.com.

411mania.com was able to get exclusive comments from referee Steve Mazzagatti, who presided over the Rob Emerson vs. Gray Maynard no contest that took place this past Saturday during the TUF 5 season finale.

In regard to the decision:

“I stopped the fight as Rob was in pain. I did not see a tap, but I don’t see what it matters. In boxing we give both fighters an 8 count and may count one or both fighters out. In this sport we don’t have an 8 count. But both fighters were done. Should a fighter who is out win? I don’t have time to think about all this stuff but I hope we can learn. I do think it was the right call.

“I also want to say the call was mine. I informed the commission that both fighters were unable to continue. That was my call.”

I still disagree with the decision. Mazzagatti didn’t even acknowledge Maynard’s condition until after the fight. He was completely focused on Emerson.

In any event, a rematch between Maynard and Emerson is already in the works, as is a possible rematch between Nate Diaz and Manny Gamburyan. However, the Diaz vs. Gamburyan may have to wait because it’s looking likely as though he’ll undergo surgery.

Update: In a previous version of this story I incorrectly stated that Loretta Hunt fromThe Fight Network had reported that UFC president Dana White was seen speaking with Mazzagatti and NSAC officials after the fight was stopped. Loretta never reported that and it was irresponsible on my part to attribute those comments to her.