Heiskanen is now the third critical player the Stars have lost for an extended period of time. Tyler Seguin is out for four-to-six months following hip surgery he had done in December, and Mason Marchment has missed a month for face surgery after taking a puck to the face in late December.

The star defenseman will likely be out for months, if not the rest of the season. Expect the Stars to struggle in his absence, and to have a much better understanding of their roster when he returns.