Embiid, Harden lead 76ers over Knicks while Mavs beat Lakers
Cameroonian star Embiid struck for 35 points and eight rebounds while Harden delivered 29 points and 13 assists in the 76ers' eighth consecutive victory.
Philadelphia improved to 20-12, fifth in the Eastern Conference, and stretched the lead over the sixth-place Knicks (18-16) despite Julius Randle's 35 points for New York, losers of three straight games.
The Knicks led by as many as 14 points in the first half but the Sixers stayed close and Georges Niang hit four 3-pointers in the fourth quarter to help ignite Philadelphia.
New York's Jalen Brunson scored 23 points and added 11 assists before leaving with an apparent right hip injury in the fourth quarter.
At Dallas, the host Mavericks got 32 points, nine rebounds and nine assists from Slovenian star Doncic in downing the Lakers 124-115 while Christian Wood added 30 points, eight rebounds and seven assists.
The Mavericks were down 54-43 at halftime before outscoring the Lakers 51-21 in the third quarter, the only quarter Dallas outscored the Lakers.
LeBron James scored a game-high 38 points with six rebounds and five assists and Russell Westbrook added 17 points off the bench but the Lakers dropped their fourth game in a row and fell to 13-20, 13th in the Western Conference.
Anthony Davis remains sidelined with a right foot injury for the Lakers.
The Mavericks used the Christmas holiday contest as the backdrop to unveiling a statue of former Dallas great Dirk Nowitzki, the German playmaker's bronze image captured making a fadeaway jumper.
Nowitzki led Dallas to the 2011 NBA crown and was the NBA Most Valuable Player in 2007.
Other NBA holiday games find Milwaukee at Boston, Memphis at Golden State and Phoenix at Denver.