"''I am honored to have such an accomplished individual join our program," Popovich said. "Coach Messina is an exceptional coach, a great leader and someone we can all learn from."

The Spurs have long been at the forefront of the NBA's international movement, bringing in players like Tony Parker from France and Manu Ginobili from Argentina to help build a championship core. Embracing that style of play, and opening their doors to players from overseas, has been one of the biggest reasons for the team's sustained success. They have won five championships and been to two straight NBA Finals.

The 54-year-old Messina has won four Euroleague championships and coached Ginobili in Italy in 2001. Ginobili posted a photo of himself and Messina on Tuesday and said he was excited to work with him again.

"12 (years) after our last game together, we meet again!" Ginobili tweeted. "Great to have him on board for another run. Welcome to SA Ettore!"

Messina is one of the most well-respected coaches in the game, both domestically and internationally.

In recent seasons, his name was raised as a candidate to become the first European coach to become a head coach in the NBA.

David Blatt beat him to it, coming over from Israel this year to coach the Cleveland Cavaliers. But Blatt is American born, so the door is still open for Messina to make a bit of history himself.