Texans safety D.J. Swearinger broke up a pass intended for Keller, going low while making direct contact with his helmet against the tight end's knee. Keller's leg bent backwards, and he was visibly shaken after the injury.
Keller will have an MRI on his leg Sunday, a person informed of the injury told NFL.com's Ian Rapoport.
The tight end, who signed a one-year, $4.25 million contract in the offseason, was slated to be Miami's starting tight end. He has shown good chemistry with quarterback Ryan Tannehill in training camp and the preseason.