Heavyweight prospect Anthony Joshua, a 2012 Olympic gold medalist for Great Britain, has suffered a back injury and been forced to pull out of a Jan. 31 clash with former title challenger Kevin Johnson at the O2 Arena in London, according to a Monday press release from Eddie Hearn of Matchroom Sport.

The 25-year-old Joshua (10-0, 10 knockouts) requires immediate medical attention and subsequent therapy as the result of a pars stress fracture in his back, according to Hearn’s statement. On the advice of his medical team and trainer, Joshua has been ordered to rest before resuming training to appear on a show scheduled for April 4.

“I trained so hard over Christmas, and the press conference with Johnson was so lively that I was really looking forward to putting in a great performance. It’s bad news for myself and for the fans that have bought tickets,” said Joshua.

“I hope to be able to put on a fan zone at the weigh-in and the fight itself to meet the fans. I will be competing many times this year, but this injury is something that I need to get sorted as soon as possible.”

Click here for a video of Joshua.

The card will go on, however, as British lightweight contender Kevin Mitchell (38-2, 28 KOs) takes on former title challenger Daniel Estrada (32-3-1, 24 KOs), middleweight John Ryder faces Les Sherrington, junior welterweight Ricky Boylan meets Tommy Martin, and 140-pound John Wayne Hibbert fights Tyler Goodjohn.

“It’s disappointing to lose Anthony from this great card, but after receiving news from the scan, he was left with no option but to rest his back,” said Hearn of Joshua, who is coming off an 86-second knockout of Michael Sprott in November.

“He picked up a niggle in the Sprott camp and had a good month rest after, but it hasn’t been 100 percent in camp, and the results gave him no option. He hopes to resume punching in early February and come back with a bang in Newcastle on April 4.”

Mitchell, 30, could earn his sixth straight victory in a run that has included four consecutive knockouts, the last coming by 11th-round stoppage over previously unbeaten Ghislain Maduma in May.

In the wake of injured beltholder Omar Figueroa Jr. being stripped and declared a “champion in recess” by the WBC, former featherweight and junior lightweight titleholder Jorge Linares (38-3, 25 KOs) knocked out Javier Prieto for the vacant 135-pound belt last month.

Estrada, 29, was last in the ring for a ninth-round stoppage loss to then-titleholder Figueroa in August, ending a nine-fight winning streak that had included five knockouts.

Ryder, 26, has won four consecutive fights since falling by unanimous decision in September 2013 to undefeated Billy Joe Saunders, who could soon face WBO titleholder Andy Lee.

Sherrington, 32, has won two straight since falling by ninth round knockout to former IBF beltholder Sam Soliman in December 2013. Sherrington is coming off last month’s unanimous decision over Samir Santos Barbosa.