Al Horford is expected to miss three to four months with a torn left pectoral muscle, according to a source.

Horford sustained the injury in the first half of Wednesday's game.

“We are very disappointed for Al and our team and we wish him the best as he moves forward in the rehabilitation process,” said Hawks’ Executive Vice President and General Manager Rick Sund in a statement. “He has contributed greatly to our success since his arrival in Atlanta, and that’s evident by his selection to the NBA’s All-League team last season (third team pick).”