SAN FRANCISCO — Al Horford is coming back to the Golden State Warriors on a two-year deal, a league source confirmed to The Athletic.Horford, who turned 40 years old earlier this month, declined a player option worth about $6 million to sign the new deal. According to ESPN, which first reported the deal, the new contract includes $14 million guaranteed and trade kickers. The news — and particularly the length of the deal — comes as a surprise given that Horford struggled to stay on the floor last season. He played in just 45 games while dealing with a variety of injuries.At his end-of-season news conference, Horford acknowledged he would take a couple weeks to decide whether he wanted to continue playing after 19 seasons in the league. Now he’s on track to become just the 13th player to play at least 20 seasons in the NBA. Horford told The Athletic before the season that he was hopeful that he would be able to finish his career with the Warriors and have one more chance to contend for a championship before his career ended, but given the current state of the Warriors’ roster — and the uncertainty surrounding Jimmy Butler’s potential return next season from an ACL injury — that seems far-fetched.What we know about LeBron James' retirement decisionDan WoikeHorford averaged 8.3 points and 4.9 rebounds per game last season and did find a better rhythm after Christmas, playing some of his best basketball of the season before another injury in March knocked him out for another long stretch.