That led to charges for McGregor, who escaped a jail term and criminal record after pleading guilty to disorderly conduct, paving the way for the bout against Nurmagomedov.
The fight comes as a relief for Dana White and his company, as they were severely lacking in star-power in McGregor's absence and watching pay-per-view numbers decline in the process.
Nurmagomedov (26-0) proceeded to overwhelm Al Iaquinta in Brooklyn to capture the lightweight belt that the UFC had stripped from McGregor.
McGregor has posted several photos on social media this week hyping his physical fitness in advance of the announcement, which neither fighter attended.
The often-outspoken Irishman has not fought in the octagon since November 2016, when he became only the third man to capture UFC titles in two different weight classes by beating Eddie Alvarez.
McGregor never defended either belt. McGregor never technically lost the lightweight championship, but rather had the belt stripped from him after his extended absence leading up to and after his boxing match against Floyd Mayweather past year.
Old-time plane crashes in Swiss Alps, killing 20 on board
Daniel Knech of the Swiss safety investigation service SESE said the crew did not have time to send out a distress signal. The mountainous area in south-eastern Switzerland is popular with hikers and skiers and includes a glacier.
The UFC dramatically announced the matchup on Friday with a promotional video to close a news conference promoting its fight cards for the rest of 2018.
And just as millions of fans will be watching the fight with interest, fighters will also be watching the UFC 229 main event attentively, including one many, including Khabib, consider the greatest of all time: Georges St. Pierre. However, considering that fight takes place on October 6, a one or two-month turnaround to fight arguably the greatest fighter to ever grace an Octagon might be too much of an ask for the victor.
McGregor will bid to reclaim the lightweight title, which he was forced to give up due to inactivity.
"It's time to roll", Diaz said following his own two-year absence. "However, I think legacy-wise, I don't think he's the guy that legacy-wise".
"I hope that there are no more provocations from McGregor", Abdulmanap Nurmagomedov told R-Sport. "It's good to have Nate back".
McGregor himself has said recently that he would prefer to fight in Madison Square Gardens again, but conceded that he believed his next fight would be in Las Vegas.