According to ESPN's Adam Schefter, Hopkins' absence was directly related to McNair's comment, but he wasn't the only one who wanted to get away from the team Friday.
Per ESPN.com's Sarah Barshop (via Schefter), Texans players had to be "persuaded" to stay at practice.
ESPN The Magazine's Seth Wickersham and Don Van Natta Jr. reported during last week's meeting between owners, team executives and Commissioner Roger Goodell that McNair said the NFL "can't have the inmates running the prison" regarding protests during the national anthem.
McNair issued an apology for his comments Friday.
"I regret that I used that expression," his statement said. "I never meant to offend anyone and I was not referring to our players. I used a figure of speech that was never intended to be taken literally. I would never characterize our players or our league that way and I apologize to anyone who was offended by it."
According to Wickersham and Van Natta, Dallas Cowboys owner Jerry Jones "was trying to build momentum for an anthem mandate resolution" during a speech that led to McNair making his comment.
"That statement stunned some in the room," per Wickersham and Van Natta.
Aaron Wilson of the Houston Chronicle reported Texans offensive tackle Duane Brown said players will reconvene at some point to determine what they want to do after deciding to practice Friday.
The Texans will travel to Seattle for a matchup with the Seahawks on Sunday.