James needed intravenous fluids after the game, during which temperatures inside San Antonio's AT&T Center were measured at nearly 90 degrees after the arena's air conditioning system failed. The Spurs won the game 110-95, pulling away in the final 3:59 after James left the game for good with cramps ravaging his left leg.
"Our apologies for our response to fans' tweets during (Thursday) night's Heat vs. Spurs game," Gatorade said in a release. "We got caught up in the heat of the battle. As a longtime partner of the Miami Heat, we support the entire team."
Gatorade has a long business relationship with the NBA. James is an endorser of Powerade, a Gatorade rival.
James was a lightning rod of social media criticism after cramping in Game 1, with even NFL player Jonathan Martin — a central figure in the Miami Dolphins' bullying scandal last year — questioning his toughness in a tweet that was quickly deleted.
"What everybody has to say, you guys should know me by now, I don't care. I really don't," James said. "I really don't care what people say about me."
One of the tweets, in response to someone who directed a message toward the sports drink's feed, read that, "We were waiting on the sidelines, but he prefers to drink something else."
He may be paid by Powerade, but it appeared James was drinking Gatorade at least once during Game 1 of the finals. Video and photos taken of James on the Heat bench during the second half showed him holding what appeared to be a Gatorade bottle with the label removed, as has been the case on many other occasions.
The original tweet posted by Gatorade came late in Game 1, saying, "With a game this hot, we're right at home."
The Spurs said a power outage was to blame for the air conditioning failure, and later NBA Commissioner Adam Silver told The Associated Press that a faulty breaker was identified as the issue. The team announced Friday it had been repaired.