Humphries, a Washington Wizards player, was married to Kardashian for 72 days before she filed for divorce in 2011.
Humphries responded in a follow-up tweet and expressed his support for Jenner.
"I have and always will support Bruce hence #Gottadoyou," Humphries said. "Now recognize I was too vague and sincerely apologize for the way this came across."
"#FullySupportBruce," he added.