The Atlanta Hawks agreed to sign Dwight Howard as free agency opened, but Al Horford had "major reservations" about playing with him.

Horford was seeking a five-year, $153 million contract with the Hawks at his full max but the team never budged and he instead agreed to sign with the Boston Celtics.

The Hawks were planning on trading away Paul Millsap in order to accommodate Howard and the re-signed Horford. 

Horford had spent his entire career since being drafted in 2007 with the Hawks.