Watson went down on a normal drill while running a read option.
Reaction after Deshaun Watson's injury
"Yesterday, I felt like I let my teammates, my fans and my family down. However, as a child of God, I understand that everything happens for a reason. He DON'T make mistakes!" Watson wrote.
The AFC's Offensive Player of the Month and the NFL Offensive Rookie of the Month also thanked his teammates, other NFL players and fans for support.
"I promise that I will continue to work diligently so that this team can one day bring a championship to Houston, and when I return, I will be better, stronger and more focused than ever before!" he added.
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