Williams was forced off with a groin problem, while winger Pino needed treatment late in the second half after hurting his shoulder, although he managed to finish the match.
According to head coach Luis de la Fuente, Williams had: "A slight discomfort. It might be a strain, or maybe just fatigue."
"The worst part is the tremendous pain we feel over what's happening with Yeremy - he might miss the (rest of the) World Cup," he added, defining what Pino did as "heroic".
Despite De la Fuente’s prognosis being pessimistic on Friday - when the coach said Pino had probably broken his collarbone - the results of tests conducted on Saturday ruled out a fracture, diagnosing a sprain instead.
"Nico Williams has suffered a muscle injury in his right adductor following a hard collision during the match against Uruguay," the RFEF statement said. "Both injuries are moderate, and their recovery will determine their availability."
Spain arrived at the tournament with doubts over Williams and Lamine Yamal, who sustained hamstring injuries in April. While Yamal has recovered steadily, Victor Munoz, who recently signed for Liverpool from Osasuna, is still waiting to make his tournament debut due to a leg muscle injury, leaving De la Fuente short of natural options out wide.
If Williams, Pino and Munoz are unavailable, he could return Gavi to the left wing, as he did in Spain's goalless draw with Cape Verde.
Another possibility is shifting Mikel Oyarzabal to the left, with Ferran Torres or Borja Iglesias starting at centre forward and Yamal on the right wing.
FIFA World Cup 2026
The 2026 World Cup is taking place from June 11th to July 19th in the United States, Canada and Mexico. The tournament features 48 national teams and is played at 16 modern stadiums.
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