Carlos Ulberg has undergone surgery after suffering a torn ACL in his stunning UFC light-heavyweight title win over Jiri Prochazka.

In the main event of UFC 327, Ulberg fought former champion Prochazka for the vacant belt, and few could have foreseen the way the bout panned out.

Ulberg, 35, sustained a serious knee issue early in round one, but he fought through that injury to knock out Prochazka in the same frame.

The Kiwi’s victory defied all odds but he will now have to wait an extended period to defend his title, if he gets the chance to defend it at all, after his manager confirmed the extent of his knee injury.

Speaking to Ariel Helwani, Ash Belcastro revealed Ulberg “snapped” his right ACL and went under the knife on Thursday for surgery that “went really well,” per his doctors.

Ulberg also experienced bone bruising and tibia damage due to the fact that he continued fighting with the torn ACL.

“He’s dedicated to getting back as soon as he can,” Belcastro said.

It is currently unknown whether Ulberg will be forced to vacate the light-heavyweight title, which would leave the division in limbo once again after Alex Pereira relinquished the gold in February to move up to heavyweight.

Prochazka, who lamented the “mercy” he showed to a clearly injured Ulberg before being caught with a bomb of a left hook, went through something similar when he won the title against Glover Teixeira in 2022.

The Czech fighter sustained a serious shoulder injury in that bout which left him on the shelf for around a year, with the UFC promptly making the decision to strip him of his title once they’d learned the extent of the problem.

An ACL tear takes around six to 12 months to fully rehab without training, meaning it is unlikely Ulberg will be able to defend his title for at least another year.

The UFC could therefore end up taking the same action they did with Prochazka four years ago and force Ulberg to vacate his title, just weeks after winning it.

Otherwise, an interim title match could be sanctioned by the UFC, as they did for the heavyweight crown.

Briton Tom Aspinall is the reigning champion but has not fought since suffering a serious eye injury in his first defence against Ciryl Gane. With Aspinall still some way off a return, Gane has been booked to face off with Pereira for interim gold in the co-main event of the White House card on 14 June.