Yan and Sterling forcefully restrained from faceoff before UFC 273 clash (VIDEO)

Russian MMA star Petr Yan and his bantamweight title rival Aljamain Sterling weren't allowed to face off at the final UFC 273 press conference and had to be separated ahead of their second title fight on Saturday.

The pair currently boast one of the elite promotion's most bitter rivalries stemming from their first meeting in March 2021.

Yan was champion then, but surrendered the belt to Sterling after delivering an illegal knee on his grounded foe which saw Yan disqualified.

Yan has since become the interim champion by beating Cory Sandhagen, and after numerous delays and social media rows, the two arch rivals will finally face off in Jacksonville at UFC 273 on Saturday.

With Yan threatening to "kill" Sterling and his team if he bumped into them beforehand, the first face-to-face meeting since their maiden bout was sure to be tense. 

As was expected, Yan marched straight over to Sterling after Thursday's press conference as Sterling welcomed Yan over with a wave. Before they could get nose-to-nose, though, a set of UFC security guards stepped in the way while Sterling and Yan mouthed at each other and fans jeered.

Before that during a heated 45-minute discussion, Yan promised fans: "I will kill him on Saturday".

Sterling, who brought an 'MMA Rulebook 4 Dummies' manual with him in reference to their first meeting when Yan kneed him, was booed but predicted that a convincing win would have MMA enthusiasts back on his side. 

"I finally get to shut this motherf**ker up," Sterling remarked. "It’s going to be so sweet. I guarantee everybody here is going to be cheering and all of a sudden, they’re going to be back on the bandwagon. So that’s the way the fans are, but I’m just glad the fans are going to tune in."

Yan was also asked to clear up his comments on Wednesday that saw him say: "If we see his team, we kill [all his] team. Right now, not Saturday."

"I just made a joke, and I’m not going to jeopardize the fight before," the 16-2 brawler clarified.

Elsewhere, on the eve of the biggest fight of his client's career, Yan's manager Danny Rubenstein insisted that 'No Mercy' is in the shape of his life to settle the score with Sterling.

"He’s great – I’ve honestly never seen him look better," Rubenstein told MMA Junkie. "I’ve had a lot of conversations with a lot of people around him, outside of him – everybody is very impressed by what he’s been doing and especially this camp and how he’s looked this camp.

"His weight is good. [He has] no injuries, which is pretty much a first for him," Rubenstein noted. "Every other fight, he’s had some kind of injury. The Jimmie Rivera fight, he was in the hospital the week before the fight. So everything has always been, with Petr, very difficult getting to the fight.

"He’s always made it there and always performed very well. But the fact that he’s healthy now and [has] no injuries, I think it’s going to be a good week for him," Rubenstein envisioned.

READ MORE: Russian UFC star Yan threatens ‘to kill’ rival in hotel (VIDEO)

Furthermore, Rubenstein also believes that Yan has learned his lesson from the first fight, when what he had worked so hard for all his career in the bantamweight belt was taken away from him through his own recklessness. 

"He knows it was a mistake, and obviously he’s paid a dear price for it over the last year," Rubenstein said. "I think he knows the rules. Aljo’s had a lot of fun with it, which is fine – it sells the fight. I don’t expect there to be any issues this fight. But Petr’s a savage – he wants to go out there and hurt you. Sometimes, slip-ups arise," Rubenstein highlighted.

Lastly, Rubenstein also ruled out the potential prospect of Yan immediately moving up to featherweight should he come out on top on Saturday.

"Mentally, it’s been a year, two years, of always looking at Aljo as the next guy," Rubenstein pointed out. "I think Petr’s ready to put that behind him and move on. I don’t know if it’s T.J. [Dillashaw] next, could be [Sean] O’Malley. He’s been on a good run.

"I think there’s a lot of options for Petr. I don’t think one of those options is going up (to featherweight), though. I know a lot of people want him to maybe challenge for the ’45 belt. I think ’35 is where he’s at. I think there are competitors at ’35, and he needs to do a little more work in that division," Rubenstein concluded.