2 critical lessons Atkinson and the Cavaliers learned from loss to Celtics

If there was any rival to dethrone the Cleveland Cavaliers, it was the best-case scenario to lose in a close game to the Boston Celtics.

Facing the reigning champions was always going to be the Cavaliers' biggest test of the season. The Celtics' endless long-range daggers and cohesive star unit counters much of what makes Cleveland special. In the first match of the Kenny Atkinson era, Boston came out on top after a spirited comeback by the Cavs forced coach Joe Mazzulla and the Celtics to throw everything at Cleveland.

After trailing by 21 points in the third quarter, the Cavaliers rallied and brought themselves within two points numerous times, but Boston's fiery roster had an answer every time. Entering the night, the Cavs held a franchise-record 15-game win streak to start the season. They had a massive target on their back, and the Celtics gave Cleveland a playoff-level competition.

Cleveland fell 120-117 in the end, nearly saving themselves before late turnovers and missed daggers cost the Cavs their perfect record. Despite the loss, the Cavaliers and the fanbase have plenty to appreciate about the night. An under-manned Cavs squad pushed the reigning champs to the final buzzer. Donovan Mitchell led his team with 35 points alongside eight rebounds.

Evan Mobley also showed his star power, adding 22 points and 11 rebounds to the scoreboard, dishing out six assists, as well. Unfortunately, the Cavs could not maximize Jarrett Allen or Darius Garland on offense, leaving both players well below their season averages in scoring.

Atkinson may have lost the chess battle with Mazzulla, but Cleveland leaves this game with more insight and advantages for their next game, and a potential playoff revenge series, than his New England counterpart.

The Cavaliers know Boston's playbook

Bringing themselves back into the game forced the Celtics to employ their end-game strategies. The Celtics are a wildly versatile and dynamic squad. Both Jayson Tatum and Jaylen Brown have MVP potential; however, they are not invulnerable. Boston has fallen short of their goals before, and the Cavaliers now know exactly how the Celtics gameplan against them.

On the other hand, the Celtics cannot know how to handle the Cavaliers, still. While the Celtics were without Kristaps Porzingis, the Cavs were without Isaac Okoro, Dean Wade and Max Strus. Cleveland's lenghty injury list did not allow them to play to their fullest potential in the late game, meanwhile the C's were nearly at their best.

Mazzulla likely has more tricks up his sleeve for KP's return, but Boston's use of Neemias Quieta as an interior presence probably indicates how Porzingis will compete against the Cavs. With two talented big men in the Cavaliers' starting five, Mazzulla will be forced to put Porzingis into the post more than he typically does. Additionally, the Cavs will likely see Boston use a two-big lineup of their own, playing both Al Horford and KP at the same time to counteract the Cavaliers.

Cleveland was without their best defensive weapon for the Celtics with Okoro sidelined. The next time the Cavs face the Celtics, it will still be a brutal challenge, but they will have more weapons at their disposal than Boston has faced under Atkinson's system.

Cleveland needs to be better on the perimeter

Both on offense and defense, the Cavaliers fell short on the arc. The Celtics did what they do best - shooting threes. They shot 41 three-pointers, knocking down 22 of them. With more than half of their deep shots falling, the Cavaliers should have mathematically stood no chance. With just 10 of their own threes hitting, Cleveland's ability to remain in the game shows a clear path to success next time.

Stopping the Celtics from shooting and making threes is no easy task. Mazzulla has evolved the long-range onslaught offense that has taken prominence in the NBA since the Golden State Warriors and Houston Rockets ushered it into the mainstream. With an average of over 50 three-pointers attempted per game as a team for Boston, the Cavs must prioritize perimeter defense more next time.

Too often, the Cavs' defensive rotations left a lethal shooter wide open on the corner or the wing. In the first half, the Cavaliers would watch the shot go up without chasing the closeout. It led to an early run for the Celtics. In the second half, Cleveland chased down shooters, but they were still too quick to overcommit on help, making the closeout useless.

Cleveland has one of the league's best defenses again this season, but Boston exposed their flaws. The Cavs have shown they have every tool necessary to be a perimeter pest. Even without their best perimeter defenders, Okoro and Wade, present, the Cavaliers must show more fight on the arc. Cleveland allowed the Celtics to put Georges Niang into isolation defense against Tatum far too many times. Although Niang has the size and strength to challenge Tatum, JT's shiftiness and handling made a mockery of Niang's efforts.

The Cleveland Cavaliers will have their second chance fairly soon, hosting the Boston Celtics at Rocket Mortgage FieldHouse on Sunday, December 1 for a 6:00 pm ET tip-off. Hopefully, Cleveland will have Okoro and Wade back and will enter the night with vengeance on their minds.