Michele Pirro will deputise for the injured Ducati rider Cal Crutchlow at this weekend's MotoGP Grand Prix of Argentina.
New signing Crutchlow has been forced to return to England for treatment after braking a finger following a violent accident during the Grand Prix of the Americas at Austin, Texas.
The Brit had hoped his injury, which was originally diagnosed as a dislocated finger, would heel in time for MotoGP's debut at Argentina's Autodromo Ternas de Rio Hondo circuit.
However, continued pain in his right hand has left him with no option but to sit out this weekend's meeting to aid his recovery.
Ducati has promoted test rider Pirro to fill the void while Crutchlow nurses his finger back to full fitness. The 27-year-old Italian has competed in 38 Grands Prix.
“I am very sad to let the team down like this because I was really looking forward to racing in Argentina,” said Crutchlow.
“On the Tuesday after Austin I had some scans on my hand and we saw that my finger was still dislocated from the crash and also broken so Dr. Chao decided to put a pin in to stabilize it.
“Unfortunately I'm still feeling too much pain in my right hand, my knuckles are the most painful part and I'm not in condition to race this weekend.”
Crutchlow is hoping to return to action at Jerez for the Grand Prix of Spain on May 4.