The Boston Celtics were cruising against the Cleveland Cavaliers on Saturday night. Then, the fourth quarter happened.
Boston blew a 19-point lead and couldn't hold on in the final minutes as they fell to the Cavs in a stunner, 91-89. The defeat snapped the C's modest two-game win streak. Meanwhile, Cleveland has now won six of its last seven games.
The Celtics will have a shot at redemption Monday in a rematch at Rocket Mortgage FieldHouse.
Here are three instant takeaways from the loss, which brings the C's to 6-7 on the season.
An inexcusable collapse
This Celtics team remains infuriating to watch in the fourth quarter.
With a 19-point lead early in the fourth, it appeared as though they were sleepwalking to their third straight win. Then, before you could even blink, the Cavs had the game tied and it looked like Boston was headed to its fifth overtime game of the young season.
While the C's avoided OT, this time they weren't on the winning side. Cleveland rallied to earn the improbable victory thanks to an alarming amount of inexcusable Celtics miscues. Boston turned the ball over eight times in the nightmare quarter and was dominated on the offensive glass.
The inability to finish games in crunch time has been a theme for the Celtics for some time now. That's a funk they're going to have to get out of, and fast.
Jayson Tatum's inconsistency continues
Tatum has the second-most points on his team with 21, but don't let the stat sheet fool you. This was not one of his better nights.
With Jaylen Brown and Al Horford out, Boston needed its star to step up on the second night of a back-to-back. But Tatum looked off throughout the contest, shooting 36.4 percent from the field (8-for-22) and turning the ball over six times.
Inconsistency has been an issue for Tatum in the month of November. Over his last nine games, Tatum is 72-of-195 from the field (37.9 percent) and 20-for-64 from 3-point range (31.3 percent). He has 25 turnovers in that stretch.
That won't cut it.
Robert Williams turning into a double-double machine
If you're looking for a bright spot in the tough loss, Robert Williams is it. Time Lord notched his third straight double-double with a 12-point, 16-rebound performance. He also added three blocks, three assists and a steal to the box score.
It wasn't a perfect outing for Williams as he struggled to grab some crucial boards down the stretch, but he was the least of Boston's problems Saturday night. He continues to be one of the most encouraging parts of the C's campaign through 13 games.
If Williams can stay healthy -- a big "if" thus far in his career -- that'll be a game-changer for the Celtics this season.
Cavs' future is in good hands
Cleveland improved to 9-5 on the season and much of that success has been the result of stellar play from youngsters Darius Garland and Evan Mobley.
Garland led the way for the Cavs in the win with 22 points and six assists. The 21-year-old was the spark plug his team needed when it mattered most.
Mobley, Cleveland's third overall pick in the 2021 NBA Draft, showed why he'll be a Rookie of the Year candidate this season. The 7-foot phenom tallied 19 points and made a major impact on the defensive side with nine rebounds, three blocks and two steals.
The 20-year-old USC product certainly looks the part. The Celtics will have their work cut out for them against him once again Monday night.
Tip-off for the rematch is set for 7 p.m. ET on NBC Sports Boston.