It will be Max Holloway against Khabib Nurmagomedov at UFC 223 for the lightweight belt as Dana White announced Sunday that the featherweight champion will step in on six days' notice to replace Tony Ferguson, who suffered a knee injury.

White told Brett Okamoto of ESPN that Ferguson requires surgery for a torn LCL in his knee, which necessitated his removal from the headline fight. This marks the fourth time that a bout between Ferguson and Nurmagomedov has been cancelled.

While some assumed Ferguson would be keeping his interim title, that doesn't appear to be the case.

The pair were initially supposed to meet in 2015 and 2016 but both bouts were cancelled due to injuries.

A highly anticipated matchup at UFC 209 was then set, but Nurmagomedov was transported to hospital the day before the fight after falling ill while cutting weight. The doctors recommended the fight be called off.

While the fourth cancellation of the matchup is disheartening, the fact that a name as big as Holloway has stepped in makes for an intriguing contest. The 26-year-old last fought on Dec. 2 when he defeated Jose Aldo by TKO in the third round.

If Holloway is able to beat Nurmagomedov, he would add the lightweight title to his featherweight crown and become just the fifth fighter in UFC history to win belts in two divisions.

Earlier this month, White confirmed the winner of the Ferguson-Nurmagomedov bout would get Conor McGregor's lightweight title.

"As soon as one punch is thrown, it's on for the full title and it's only fair," White told Lance Pugmire of the Los Angeles Times.