NBA Christmas schedule: Everything to know for the five-game holiday showcase

The NBA campaign officially started two months ago, but it's said the season really starts on Christmas Day. As football season enters the stretch run, more fans tune in to the NBA, and it starts with the league's annual holiday showcase.

This year features a five-game slate that was much more impressive when the league announced it in August. Injuries will have a major impact on three of the games, leaving some of the league's biggest names on the sideline Wednesday.

Luckily the remaining games feature two of the most highly-anticipated matchups of the season that could both serve as previews of the conference finals. So once all the presents are opened, put on your new slippers, pour yourself some eggnog and settle in for a day of basketball.

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Celtics at Raptors (noon ET, ESPN)

The defending champion Raptors will make their first Christmas Day appearance since 2001, but they'll be without their best player and one of the league's rising young stars. Pascal Siakam, last season's Most Improved Player, suffered a groin injury last week and is out indefinitely. Fellow starters Marc Gasol (hamstring) and Norman Powell (shoulder) are also out for Toronto.

The Raptors will get little sympathy from the Celtics, who have dealt with significant injuries of their own so far this season. However, Boston expects to have Gordon Hayward (foot) back in the lineup Wednesday after missing three games.

Bucks at Sixers (2:30 ET, ABC)

Two top Eastern Conference contenders face off for the first time this season. Reigning MVP Giannis Antetokounmpo and the Bucks carry an NBA-best 27-4 record into Christmas Day, putting them on pace for 71 wins. The 76ers haven't played up to expectations yet this season, but they remain a formidable presence with one of the league's best defenses.

Antetokounmpo always seems to rise to the occasion against marquee opponents, and he torched the Sixers for 43 points, 15.7 rebounds and 7.7 assists in three games last season, including a career-high 52 points on March 17. Philly big man Joel Embiid countered with 34.7 points, 15.7 rebounds and 8.3 assists in the three meetings. Here's hoping they give us something similar on Wednesday.

Rockets at Warriors (5 ET, ABC)

Of all the Christmas Day games, this one might be the most drastically different on paper than it was when it was scheduled. Decimated by injuries, including to superstars Steph Curry and Klay Thompson, the Warriors have fallen to the bottom of the Western Conference standings. Rookie Eric Paschall, one of Golden State's few bright spots this season, is questionable to play Wednesday.

On the other side, Houston star James Harden has been as good as ever. He enters the game averaging a league-leading 38.8 points per game and has the Rockets offense humming even as they continue to integrate Russell Westbrook into the lineup.

Clippers at Lakers (8 ET, ABC)

The latest meeting of the Staples Center rivals gets the prime time slot on the Christmas Day schedule and may be the most anticipated game of the regular season. They met on opening night, but with everyone now available, Wednesday will be the first full-strength matchup between the teams most expect to meet later this spring in the Western Conference finals. 

Not much more needs to said about this game other than LeBron James and Anthony Davis against Kawhi Leonard and Paul George. With four of the biggest names in basketball, the matchup won't lack star power. Given the Lakers' and Clippers' championship aspirations this season, neither team will likely put much stock in the result. But fans are certainly hoping for a sneak peek of the playoff series we all expect in five months. 

Pelicans at Nuggets (10:30 ET, ESPN)

The holiday extravaganza concludes with the last game marred by injury. Pelicans top pick Zion Williamson remains sidelined after offseason knee surgery, and his absence has been a blow for a league that initially scheduled New Orleans on national television 30 times. The Pelicans have struggled and sit in the bottom five of the league.

However, a bright spot for New Orleans has been the ascent of Brandon Ingram, who is blossoming into a star after being acquired in the Anthony Davis trade. He'll face a test against a Nuggets team that has quietly remained in the top four in the West behind Nikola Jokic, Jamal Murray and the continuity of an almost-entirely unchanged roster. 

Follow Matt Eppers on Twitter @meppers_.