MIAMI — This certainly has been a unique Miami Heat experience for Josh Christopher. The veteran NBA guard has yet to play a single regular-season game for the Heat, but already has competed for two championships in the team’s colors. Having earned a two-way contract after leading the Heat’s entry to the Las Vegas NBA Summer League championship in July, Christopher found himself chasing a second championship in Heat colors on Sunday night at the G League Showcase in Orlando. Through it all, the former 2021 first-round pick of the Houston Rockets went into the week yet to appear in a game for the Heat, unlike the team’s other two-way players, guard Dru Smith and forward Keshad Johnson. So, instead, Christopher has played as the anchor of the Heat’s G League affiliate, the Sioux Falls Skyforce.