PHILADELPHIA – The running joke during Nikola Jovic’s rookie season was that he hadn’t yet graduated high school. With diploma secured back in Serbia last summer, the higher education of the Heat’s 2022 first-round pick immediately began this season. So perhaps it was only fitting that the Heat’s practice ahead of Wednesday night’s play-in game against the Philadelphia 76ers came at Temple University. The mere opportunity to be schooled during his sophomore NBA season was reason enough for pomp and circumstance for the 6-foot-10 big man. “He’s gotten a lot better with his defensive fundamentals,” said coach Erik Spoelstra, with Jovic not turning 21 until June.