The Spaniard, a four-time Grand Slam winner, sustained the problem during his Barcelona Open final defeat last Sunday by Holger Rune.
“I did everything that was in my hands but it didn’t improve a lot over the (last few) days,” Alcaraz told a news conference. “Things didn’t work out as I wanted to be able to play here, and we have decided not to take risks.
“If I played, I was going to be messed up for longer than expected – hard decisions had to be made, and I think we made the right one.”
Alcaraz was hoping to lift the trophy in Madrid for the third time after his 2022 and 2023 victories.
The 21-year-old had not trained all week after arriving in the Spanish capital on Monday.
Alcaraz did not rule out competing in the Italian Open and said he was sure he would make the French Open, with the main draw beginning on May 25.
“I think I will definitely be at Roland Garros and I will do everything possible to be in Rome,” said Alcaraz. “On Monday I’ll have another test to see how it’s evolved, and from there we’ll take the timings and evaluate how the next few weeks are going to be and how my body is doing.”
Alcaraz said in addition to the right thigh injury he suffered in Barcelona he had also noticed a problem with his left hamstring.
He has struggled for consistency over the first few months of the year, knocked out early in Miami but then winning the Monte Carlo Masters in April.
“It was the first year I went really far in Monte Carlo but it was also the first year I lost in the first match in Miami, so I had time to prepare for the clay season,” Alcaraz said.
“It is not easy – a different surface, coming from hard court to clay court and playing so many matches in a row and having no time to rest, is not easy,” he added. “Tennis players have to take difficult decisions sometimes.”
Alcaraz won every match he played in Barcelona in straight sets until the final against Rune, which he lost 7-6 (8/6), 6-2 after needing a medical time-out to treat his thigh.
“Mentally I think I’m strong to play good tennis again, so this is not going to take my confidence away,” Alcaraz said.
“If I don’t play Rome, or if I don’t play any tournaments before Roland Garros, I don’t care about it. I know what is my level, I know what I have to do to play good tennis,” he added. (AFP)
