Dunham was supposed to meet Kenny Florian, but a knee injury knocked Florian from the bout, giving Melvin Guillard the welcome opportunity to prove he's rounded into a fully matured fighter.
The challenge for Guillard will be in finding holes in Dunham's game. Sherk essentially beat him with takedowns and a bit of help from the judges. No one else has yet figured out how to beat him.
To date, the 29-year-old Dunham (11-1) has shown a well-rounded arsenal. His boxing has progressed well, with the southpaw featuring a straight left down the pipe that usually finds its target. While he doesn't have a traditional wrestling background, he seems to have good instincts about when to transition into takedowns, and he defends his opponents' takedown tries very well. The ground game is where he shines, with the Brazilian jiu-jitsu black belt earning six of his 11 wins by submission.
By contrast, the ground is where Guillard has struggled the most. At 26-8-2 with 1 no contest, the 27-year-old Guillard has been forced to tap out seven times. Anytime the fight goes to the mat, the edge will go to Dunham.
The question then, is can Dunham get the fight to the ground?
According to Compustrike, Dunham has been successful on six of eight takedown tries over his five UFC bouts. Once he gets the fight there, though, he takes advantage of it, attempting six submissions and moving into dominant positions seven times.
Guillard's opponents have had success taking him to the ground. In his last seven fights, his foes have scored on 10 of 18 tries (56 percent). He's going to have to do better than that to give himself a realistic chance to beat Dunham. While Guillard has shown the ability to quickly return to his feet, fighting on the defensive is no way to win a fight in the judges' eyes.
The standup portion of the fight will be much more interesting.
Dunham has never in his career faced a fighter with the power of Guillard, who has 16 of his 26 wins via KO or TKO, a very high percentage for a lightweight. Even during his time in the UFC, he's yet to face an opponent who is considered a big hitter. While he's had tough fights against the aforementioned Sherk as well as Tyson Griffin, those guys are both considered grinders rather than sluggers, so any questions about his chin may find some answer against Guillard.
In his last fight -- against Jeremy Stephens at UFC 119 -- Guillard fought a much more tactical style than usual. Gone was the recklessness that made him so wildly inconsistent during most of his career. Instead, he was patient, carefully picking his shots against the dangerous Stephens, on the way to a win.
It will be interesting to see how he approaches Dunham. On one hand, if he can goad Dunham into a standup battle, he's got to feel that style would favor him. He's considered heavy-handed; Dunham is not. On the other, a matured Guillard has recognized that such a reckless mind set could leak into other parts of his game and leave him open to mistakes.
Still, a standup fight brings the very real possibility of a Guillard upset win. He undoubtedly has faster hands and more power, and his chin has already stood up to many past wars, where Dunham's is still a question mark.
The X-factor in this fight might be its pace. Dunham usually likes to step on the gas pedal early, and keep it there for the entirety of the fight. Guillard's stamina was once a problem, and though it seems he's corrected it, he might find Dunham's relentless, high-pressure style draining if the fight drags into the third round.
Guillard's powerful striking makes him a threat to win any fight by knockout, but Dunham's all-around versatility is a lot to handle, and his attacking submission game will be a major test. Guillard's a live underdog if the fight stays standing, but nearly every fight ends up on the ground at some point. It is the place where Guillard has struggled and Dunham does his best work, so Dunham via third-round tapout is the pick.