Christmas Day has long been the most important date on the NBA's regular-season schedule, a chance for the league to showcase not only its best teams, but its newest rivalries. This season will be no exception, as Adrian Wojnarowski of ESPN reports that the Los Angeles Lakers will battle their Staples Center co-tenant, the Clippers, on Dec. 25. The Clippers landed Kawhi Leonard and Paul George in free agency this offseason, both former targets of the Lakers who turned them down. The two teams are widely viewed as the favorites in the Western Conference, and their battle will be the headline matchup of the day. In fact, Shams Charania of The Athletic reports both teams will also face off on opening night of the NBA season.

But that isn't the only important game set for Christmas. Zion Williamson will also make his holiday debut against the Denver Nuggets, last year's No. 2 seed in the Western Conference. According to Tim MacMahon of ESPN, the last Western Conference game set for Christmas will be a rematch between the Houston Rockets and Golden State Warriors in San Francisco. The two teams have met in each of the past two postseasons, but with Russell Westbrook joining the Rockets and D'Angelo Russell replacing Kevin Durant on Golden State's roster, there will be plenty of new faces this time around. 

Not to be outdone, the Eastern Conference will reportedly see its two presumptive favorites square off. According to Malika Andrews of ESPN, the Philadelphia 76ers will host the Milwaukee Bucks in a game that could serve as a preview for the Eastern Conference Finals. Last year's Eastern Conference champion, the Toronto Raptors, will also play on Christmas as they will host the new-look Boston Celtics

Typically, the league tries to let its defending champion host the day's marquee game. Had Kawhi Leonard remained in Toronto, the Raptors probably would have done so. But his Clippers may ultimately hold the primetime slot for their game against the Lakers. The league made sure to squeeze the defending champions onto the schedule, though, and given the moves that both sides made this offseason, the game should be an intriguing one. 

Surprisingly left off of the schedule, assuming the league holds to five games as it usually does, were the Brooklyn Nets. They landed Kyrie Irving and Kevin Durant in free agency, but with Durant expected to miss the season while recovering from his torn Achilles tendon, the NBA is holding off on giving them one of the most important regular-season dates on the schedule. 

Fortunately, the slate as presented does not lack for new faces. Seven of the 10 teams playing on Christmas acquired either a former All-Star this offseason, or a player with future All-Star potential in Williamson. Each of these games would draw significant interest on their own. Together, they form perhaps the best set of regular-season games a single day has ever held.