Chris Paul, whose Houston Rockets are in the middle of a deep playoff run, was vocal about the mass shooting, saying that the postseason right now is taking a backseat to this tragedy.
"Our prayers go out to the victims and the families having to deal with that situation," Paul said, adding the Rockets get a lot of support from the Santa Fe community.
CP3 on Santa Fe: 'The playoffs are just minor right now'
Paul later tweeted, "We need to do better by our children. #BiggerThanBasketball"
The Rockets and the Fertitta family tweeted their thoughts for Santa Fe.
The Houston Astros, who begin a series at home Friday, said it will hold a moment of silence before the series-opening match. Texas flags at Minute Maid Park will also fly at half-staff "in support and memory of the victims and their families."
Astros plan moment of silence
Astros express sympathy for Santa Fe victims
Astros players like Carlos Correa also expressed sympathy for the victims.
Manager A.J. Hinch expressed frustration over the latest school shooting in the U.S.
"It makes me sick," Hinch told reporters Friday. "Lives are being lost for no real, good reason. There's never a good reason."
Astros' Hinch: 'It makes me sick'
The Houston Texans, in the midst of offseason workouts, said they are "saddened by the tragic events at Santa Fe High School." They paid tribute to emergency workers who responded to the tense tragedy.
The NFL team's captain J.J. Watt expressed his horror of the situation with a two-word tweet.