"I have been working in Monte Carlo and trying to recover until the last minute from an injured pronator teres in my right arm, but it was not possible and I cannot play," he wrote on X.

The 20-year-old Spaniard, whose last match came in the straight sets defeat by Grigor Dimitrov in Miami last month, was due to go straight into Wednesday's second round in Monte Carlo against Canadian Felix Auger-Aliassime.

He will be replaced in the draw by Italian Lorenzo Sonego, who was drafted in as a lucky loser, the ATP announced.

"I was really looking forward to playing... See you next year!" concluded former world number one and two-time Grand Slam winner Alcaraz, who has yet to win a single match in his career at the Monte Carlo Masters.

In 2022, he arrived exhausted after his successful American tour - he reached the semi-final in Indian Wells and won in Miami - and lost his opener to American Sebastian Korda.

Last year, he withdrew just before the start of the tournament.

This time, Alcaraz waited until the third day to announce his withdrawal, which seemed inevitable given his recent training sessions, looking weak on Sunday and Monday when he did not play a single rally.