Tannehill was forced to leave Thursday's practice early after suffering a non-contact leg injury, Barry Jackson of the Miami Herald reports.
Tannehill's awkward fall occurred on a scramble to the sideline during team drills, but the quarterback was ultimately able to leave the field slowly under his own power. The severity of the injury is unknown, and he was immediately replaced by Matt Moore. The left knee injury that kept Tannehill out for the latter portion of the Dolphins' 2016 campaign hasn't been an issue throughout training camp, but he's now dealing with another left leg injury that could put his availability in jeopardy.