Lamont Jacobs pulls out of Diamond League showdown with Fred Kerley due to back problem

The Italian was set to make his first appearance in an outdoor event this year after a "winter of intense preparation" having withdrawn from last year's World Championships before the semi-finals due to a thigh injury.

"I am forced to skip the debut 100 meters and the first face off with Kerley in Rabat, which I was really looking forward to, due to a lumbo sacral nerve block that I'm working on resolving in the short term," Jacobs said in a statement on Thursday.

"It's the result of a misstep and not an injury, which does, however, keep me from competing in Morocco."

Jacobs said he was still in strong physical shape and ready for a great outdoor season.

"The challenge is only postponed," he added.

American Kerley began his Diamond League campaign by winning the 200 metres in Doha earlier this month.

The next meet is the Golden Gala on June 2nd in Florence, Italy, a meet Jacobs had previously said he would take part in.