The world No 2 prevailed 6-4, 6-2 against 130th-ranked qualifier Otto Virtanen in his first match at the ATP 500 event, but he encountered more trouble than the scoreline suggests.
After fighting off four break points across his first three service games, Alcaraz called for the physio during the changeover after he held for 5-4.
Alcaraz was heard telling the physio that he felt a “sharp” pain in his right wrist and forearm area and that he was experiencing discomfort when he hit forehands.
The seven-time Grand Slam champion had cream applied to his forearm area and received a massage before he continued.
The Spaniard lost just two games thereafter, but it was a concerning moment as he played his sixth match in just eight days following his run to the Monte Carlo Masters final last week.
In his press conference, Alcaraz pointed to the quick turnaround from Monte Carlo to Barcelona when asked about the discomfort he experienced.
“Well, to be honest, it’s been tough, it’s been a bit of a struggle,” said the 22-year-old.
“In the end, my first contact with Barcelona was this morning, for about an hour, and then I had to jump right onto the court to compete, and the conditions are completely different.
“It was a little difficult, especially at the beginning, to get into a good rhythm, a good rhythm, but little by little I think we started feeling better, adapting more and more to the conditions in Barcelona and ending up playing at a good level.
“It’s just discomfort, discomfort that pops up, considering the few days I’ve had to recover, when everything has been practically back-to-back, so in the end things come up in some unusual movements.
“We’ve tried to calm ourselves down, try to keep going, and above all, be more relaxed, especially in the second set, and see what happens. Now the physio will see me, we’ll talk with the team, and we’ll see.
“It’s a discomfort I’ve had before, which has never led to anything more serious, so let’s hope it’s the same this time.”
The two-time Barcelona Open champion will have a day to rest before his second-round match against Tomas Machac on Thursday.
Alcaraz added: “My plan is to rest if necessary, but the main goal is to try to be in the best possible shape to play and be ready for Thursday.”
