Bellator 155 took over the CenturyLink Arena in Boise, Idaho, Friday, bringing a middleweight title clash between champ Rafael Carvalho and challenger Melvin Manhoef with it.

This main-event fight promised fireworks, but promises are made to be broken, after all.

The two started off slowly – so slowly, in fact, referee "Big" John McCarthy had to halt action to remind them why they were there, encouraging them to pick up the pace. In Round 2, Manhoef began to open up with hard kicks to the legs and to the body of Carvalho. In the closing moments of the round, however, Carvalho jumped in with a knee to the body of Manhoef, appearing to catch him low. Just as McCarthy put his hands on the fighters to give Manhoef time to recover, Carvalho landed a standing elbow, causing a brief flare-up. Carvalho claimed innocence, and the fight went on.

In Round 3, Carvalho again battled the rulebook, catching Manhoef with an open hand and poking him in the eye. The two separated, but when the action resumed, Carvalho appeared to poke Manhoef again, prompting a moment of disbelief from the Dutch kickboxer. Ultimately, McCarthy never saw the second poke, and the fighters continued.

Midway through Round 3, Carvalho managed to drag Manhoef to the canvas with a body lock. Manhoef, however, quickly worked to his feet, and they worked against the cage, where the champ then landed a knee to the groin of Manhoef. Still, no point deduction. Action resumed, and Manhoef found success with his hands toward the end of the round, catching Carvalho with a heavy uppercut to close out the frame.

Carvalho turned to his grappling in Round 4, taking Manhoef to the mat and working from side control early before returning to his feet. From there, more inactivity ensued. The crowd got restless, but neither fighter seemed to mind. In a moment of pure apathy, the two walked away from each other with approximately five seconds to go in the round, choosing their corners over a chance to win – or to defend – the title.

To close out the affair, Carvalho and Manhoef traded takedowns, with neither fighter able to mount any significant offense from top position. It was a fitting finish for this fight, as nothing of note happened in the final frame.

Ultimately, the champ retained his title via split decision, much to the chagrin of Bellator commentators Sean Grande and Jimmy Smith.

"I'll say it, Jimmy: The only thing more disappointing than that fight was that horrendous decision," Grande said.

"I am disgusted that this fight went this way for Rafael Carvalho," Smith echoed. "I am disgusted for the sport right now. That's all I can say about it – that I can say on TV."

Before Carvalho's questionable title defense, Pat Curran threw himself back into the mix at featherweight with a unanimous decision victory over Georgi Karakhanyan. The former champ dropped Karakhanyan midway through Round 1, nearly earning the quick TKO finish. Karakhanyan regrouped quickly, though, and he held on to see the round's final bell.

While Karakhanyan finished strong in Round 3 with some stifling top control, it wasn't enough, as Curran's big Round 1 and his positional control on the mat throughout Round 2 earned him the judges' nod.

Before the night's co-main event between Curran and Karakhanyan, Augusto Sakai and Dan Charles fought to a majority draw. While Sakai largely controlled the distance and the action throughout, consecutive low blows in Round 1 caused him to lose a point, ultimately costing him the decision. Two would-be 29-28 scorecards became 28-28's, and now Sakai's previously undefeated record will boast a slight smudge.

Marloes Coenen was scheduled to face Julia Budd for Bellator's inaugural featherweight title, but Budd suffered an injury and was replaced by Alexis Dufresne. The changes didn't end there, though, as Dufresne then missed weight, deeming the fight a catchweight affair.

Switch-ups aside, the bout delivered, as Coenen and Dufresne engaged in an entertaining, back-and-forth grappling match until the finish in Round 1. Dufresne scored the bout's first – and only – takedown, but Coenen reversed position with a sweep. That was the beginning of the end for her, though, as Dufresne went to work from her back, securing the fight-ending triangle-armbar. In a massive upset, Dufresne proved she can potentially become a contender for the Bellator 145-pound title moving forward.

Budd, however, wasn't thrilled with upset.

Noooooooo — Julia Budd (@JuliaBudd) May 21, 2016

Heavyweights Joey Beltran and Chase Gormley kicked off the main card on SPIKE TV. While many expected an all-out, rock 'em, sock 'em affair from the opening bell, the action was relatively mild, with Gormley using a looping overhand right and a variety of kicks to keep Beltran at range. Beltran came on strong in Round 3, clipping Gormley with a massive right hand, but it was too little, too late, and Gormley took home the split-decision victory.

During preliminary action, Marcin Held evened his series with Dave Jansen. The Polish lightweight lost a unanimous decision to Jansen at Bellator 93, but three years of high-level experience paid off. After battering Jansen for three rounds on the feet and on the ground, Held took home a unanimous decision of his own.

View the full Bellator 155 results here.