A flyweight title bout between champ Demetrious Johnson (17-2-1 MMA, 5-1-1 UFC) and John Moraga (12-1 MMA, 2-0 UFC) now is on hold.

An injury to Johnson has forced him out of the fight with Moraga in the main event at the TUF 17 Finale, which takes place April 13 at Mandalay Bay Events Center in Las Vegas.

MMAjunkie.com (www.mmajunkie.com) on Tuesday night first reported the fight was in jeopardy, citing Nevada State Athletic Commission Executive Director Keith Kizer, who said that a UFC official informed him that the bout may not happen. Later Tuesday, UFC officials announced Johnson’s injury and the fight’s removal at UFC.com.

The nature of Johnson’s injury was not disclosed, nor was a timetable for his possible return. The UFC said it plans to announce a new main event for the card in the coming days.

Johnson this past month defended his 125-pound title at UFC on FOX 6, winning a unanimous decision against John Dodson in the headliner of the Jan. 26 event in Chicago. Prior to that, he won the inaugural flyweight title with a split call over Joseph Benavidez at UFC 152.

Moraga has won his past two outings in the octagon. He debuted this past August with a first-round TKO of Ulysses Gomez, then followed up with a third-round submission of Chris Cariaso at UFC 155 that won him a $65,000 performance bonus. All in all, he boasts a seven-fight win streak.

For more on The Ultimate Fighter 17 Finale, stay tuned to the UFC Rumors section of the site.

(Pictured: Demetrious Johnson)