Belinelli was always likely to leave, as the Spurs made it a priority to get enough cap space to sign LaMarcus Aldridge instead of bringing back their own free agents. After playing two years for a relatively small salary, Marco was also looking for a big contract, likely the only one he will get in his career. He gets that in Sacramento, where he will get paid in excess of $6 million a year.
Belinelli had his best years as a pro in San Antonio, where his shooting gave the bench another weapon with which to punish opponents. In his first year with the team, he shot a blistering 43 percent from beyond the arc during the regular season and 42 percent in the playoffs, helping the Spurs win a title with timely buckets on a reduced role. Last season he struggled with injuries and never reached the level he showed on 2013/14 but was still a valuable rotation player. He will likely have a similar role in Sacramento, where his shooting is sorely needed.
With Aron Baynes signing in Detroit, Tiago Splitter traded to the Hawks and now Belinelli joining the Kings the Spurs have lost three members of their latest championship team. A couple of more might be on their way out as well. Pop wasn't kidding when he said the team was going to look different after the offseason.
Good luck in Sacramento, Marco, and thanks for everything.