Scary news for Tua Tagovailoa ... the Dolphins star has been diagnosed with yet another concussion.
Miami head coach Mike McDaniel just confirmed his quarterback sustained the head injury in the 26-20 loss to the Packers on Sunday ... and is now out for the team's game this weekend against the Patriots.
McDaniel was somber in delivering the news to a gathering of reporters on Wednesday ... saying, "This is a private time for him to focus on his health."
"And," he added, "that's all I really want to get into.