Spain duo Alvaro Morata and Dani Carvajal were unwell ahead of their FIFA World Cup opening 7-0 thrashing of Costa Rica, as per the Mirror.
Morata, 30, and Carvajal, 30, were selected on the bench for the start of their demolition of Los Ticos.
The pair had caught colds from the air conditioning units in Qatar.
Atletico Madrid striker Morata was introduced into the game in the 74th minute, replacing Gavi.
Meanwhile, Real Madrid right-back Carvajal spent the entire match on the substitutes' bench.
There were question marks over Enrique's decision to start Ferran Torres and Cesar Azplicueta over Morata and Carvajal.
The pair had been first choices heading into the tournament in Qatar.
The effects of the Qatari climate affected the duo due to the air-conditioning units at the team's base at the Qatar University Hostel.
Temperatures in the Middle Eastern country are dropping to around 23 degrees at night, peaking at around 32 degrees during the day.
The air-conditioning units have been hard at work trying to aid players in the heat.
Spain put in a superb performance that showed their intentions to be a problem at the FIFA World Cup.
They recorded the biggest win in tournament history with their 7-0 destruction of a poor Costa Rica side.
Dani Olmo, Marco Asensio, Ferran Torres (2), Gavi, Carlos Soler, and Morata were all on the scoresheet as Luis Enrique's men romped to victory.
The win propelled Spain to the top of Group E, ahead of Japan on goal difference by six goals.
La Roja next face Germany on Sunday, 27 November, in what is a tantalizing clash between two European heavyweights.
The Germans suffered a shock 2-1 defeat to Japan in their opener and will be eager to bounce back against Spain.
Spain manager Enrique is asked about starting an OnlyFans account during his FIFA World Cup Twitch stream
Enrique is perhaps one of the most down-to-earth coaches at this year's FIFA World Cup.
The former Barcelona manager is holding regular Twitch streams to take questions from fans during Spain's FIFA World Cup campaign in Qatar.
One supporter asked Enrique when he is starting an Onlyfans account, a content-purchasing website that sex workers primarily use.
The Spain boss responded (via Barca Universal):
"That's a dating app, right? I've already done that enough in my life."
A guest in the same room then laughed, to which Enrique replied:
"You laugh too much! Why are you laughing?"
Enrique will hope his side continues to do their talking on the pitch as they set their sights on winning their second FIFA World Cup.
Their last triumph came in 2010 when La Roja beat the Netherlands 1-0 in the final at Soccer City in Johannesburg.