Marc Marquez will miss this weekend's Grand Prix of the Americas as the Repsol Honda rider continues his recovery from a hand injury.
The six-time MotoGP™ champion suffered a fracture to the first metacarpal bone in his right hand in last month's Portuguese Grand Prix.
He underwent surgery and subsequently sat out the Argentine Grand Prix.
Marquez had been expected to return at the Circuit of the Americas in Austin this week, but he announced on social media on Tuesday that his injury has not yet fully healed.
"I have just had a CAT scan and it was confirmed that the bone is still in the process of healing," he said.
"After talking with the medical team led by Dr. Ignacio Roger de Ona, we have decided not to take any risks and therefore I won't be able to ride in Austin.
"I will continue working and rehabilitating as I have been doing so far to be able to get back on the bike as soon as possible."
Marquez suffered the injury after a crash with Miguel Oliveira early on in Portimao, with the Spaniard found guilty of irresponsible riding for his part in the collision.
The 30-year-old was handed a double long-lap penalty and the FIM confirmed Marquez will serve the sanction when he next features, though Honda lodged an appeal.
The Spanish Grand Prix on April 30 has now been earmarked for Marquez's possible return.