Christmas Day was about more than a rivalry matchup for the Boston Celtics. Yes, they were scheduled to face the Philadelphia 76ers in what ultimately developed into a disappointing loss, but they were also gearing up to face a former draft pick in Guerschon Yabusele.

As a dangerous January schedule looms, Boston hasn't been playing up to its standard recently, falling 4 games out of first in the East.

The Celtics fell to 6-5 in December after a 118-114 loss to the 76ers in a Christmas clash at TD Garden. "We've got to look in the mirror," said Jayson Tatum.