The return of the Spanish Grand Slam record champion Rafael Nadal to the tennis tour is further delayed. After his hip flexor injury, which has forced him to take a break since the Australian Open, the 36-year-old will also miss the start of the European clay court season at the ATP Masters 1000 in Monte Carlo (8-16 April). "I'm not ready to play at the highest level yet," Nadal wrote on Twitter.

Nadal has won the Masters in the Principality eleven times, but his last triumph in Monaco was five years ago. The clay court king has only played at the United Cup in Australia and the Grand Slam tournament in Melbourne this year and has won only one of his four matches. Most recently, Nadal had fallen out of the top 18 of the world rankings for the first time in 10 years.

Alcaraz is also out

He now wants to continue his preparation for the comeback, Nadal said. He still has time until the peak of the clay court season: The French Open begins on 28 May.

Last year, Nadal won his 14th title in Paris. Overall, it was his 22nd triumph at one of the four Grand Slam tournaments. He shares the record with his Serbian long-time rival Novak Djokovic.

Also on Tuesday, Nadal's compatriot Carlos Alcaraz cancelled his start in Monte Carlo. The 19-year-old US Open champion, who lost the lead in the world rankings to Novak Djokovic after his semi-final exit at the Masters in Miami, suffered from "post-traumatic arthritis in the left hand and muscular discomfort in the spine," as he announced on Twitter.