According to Mundo Deportivo, the temperature was around 34°C during Valencia's match against Barcelona, and a yellow heat warning was issued locally.

The La Liga Matchday 4 fixture was played at Mestalla Stadium. The decision to schedule the match on a hot afternoon sparked questions over player protection and fixture planning.
On the morning of the match, the Valencia regional weather department continued to maintain the yellow heat warning and said the hot conditions would continue throughout the match period.
Playing a professional match in temperatures above 30°C can place additional strain on players' bodies. Players usually cover around 10 kilometers in a match and must repeatedly accelerate, sprint, stop suddenly, engage in physical contests and change pace, while their bodies also regulate their temperature.
The match included water breaks to allow players to drink and cool down, reducing the impact of the heat. However, Mundo Deportivo argued that since special measures were needed to protect players, it was necessary to question why a high-intensity match was still scheduled during the hottest part of the day.
The heat affected not only the players on the pitch, but also the thousands of fans in the stands at Mestalla Stadium, while an official weather warning was also in place that day.
The football world has paid increasing attention in recent years to player workload issues, including more congested schedules, reduced recovery time and rising injury risks. With the possibility of adjusting the schedule, the fact that this match still kicked off in around 34°C heat made it more controversial.
The match proceeded normally, with water breaks and medical monitoring measures also carried out, but debate over the kickoff time arrangement has not subsided. Mundo Deportivo concluded by writing that the weather cannot be controlled, but match times can be.