BARCELONA, Spain -- Carlos Alcaraz withdrew from the Barcelona Open after undergoing a test on his right wrist, the tournament announced Wednesday.
The withdrawal means the second-ranked Alcaraz cannot overtake top-ranked Jannik Sinner and move back atop the rankings next week.
The move came a day after Alcaraz called for a trainer and had his wrist treated during his opening match, a 6-4, 6-2 victory over Otto Virtanen.
Alcaraz was slated to play Tomas Machac in the round of 16 on Thursday.
The 22-year-old Spaniard lost the No. 1 ranking after Sinner beat him in the Monte Carlo Masters final on Sunday.
Alcaraz's next tournaments are the Madrid Open and the Italian Open before defending his French Open title.
Machac advances to the quarterfinals and will meet either Andrey Rublev or Lorenzo Sonego.