Jayson Tatum, Celtics Wow Fans as Mitchell, Cavs Lose 1st Game of Season in NBA Cup

The NBA's last undefeated team has fallen.

The Boston Celtics beat the Cleveland Cavaliers 120-117 on Tuesday in the NBA Cup, ending the Cavs' historic win streak at 15 games. It was tied for the second-best start to an NBA season ever, just behind the 2015-16 Golden State Warriors who won 24 straight.

Cleveland looked as if it would be handed its first loss easily as it trailed 65-48, but the resilient bunch came storming back in the second half and ultimately cut it down to a two-point game in the fourth quarter.

After a few minutes of back-and-forth, the defending champs pulled away before holding off a late surge from Cleveland.

The Celtics looked to star Jayson Tatum in the win as he dropped 33 points with 12 rebounds and seven assists. Al Horford had 20 points, Derrick White put up 19 and Jaylen Brown added 17 points and eight assists.

Donovan Mitchell had another outstanding night with 33 points and Evan Mobley added 22, but it wasn't enough to keep their undefeated season alive.

After the win, fans praised the Celtics for handing the Cavaliers their first loss of the year.

The Celtics made a statement with Tuesday's win, reminding the NBA that the East still runs through them even if the Cavs were off to a historic start.

But there's a long season ahead and Cleveland will have a few more chances to go up against the defending champs and prove themselves.

While it's still early, the Celtics and Cavaliers have clearly established themselves as the top teams in the East and we could be in for an exciting conference finals matchup in a few months.