WATCH: Jayson Tatum Dazzles, Jaylen Brown Dominates In C's Summer League Win Over Markelle Fultz's 76ers

By Michael Hurley, CBS Boston

BOSTON (CBS) -- It's not often that you get a summer league opener with as much star power as the one that took place on Monday night in Utah. It's even rarer for that matchup to actually deliver the goods.

Yet, such was the case when Jayson Tatum and the Boston Celtics took on Markelle Fultz and the Philadelphia 76ers in Salt Lake City.

Fultz -- the No. 1 overall pick of the Sixers after the Celtics traded the pick away -- looked somewhat like the star he's supposed to be, finishing with 17 points in 21 minutes. That came on 6-of-16 shooting, and he added one assist and two rebounds while tying a team high with four turnovers.

Tatum -- selected third overall by the Celtics after executing that trade -- had the better night in this first meeting, as he dropped 21 points in 33 minutes (8-of-17 shooting) while grabbing seven boards and making three assists. He was credited with five steals while committing just one turnover.

He also made this thunderous dunk:

He made a mid-air switch en route to scoring his first bucket:

And, most notably, he drained the game-winning shot in the game's final second when the Celtics trailed by a point:

(Paul Pierce likely believes that was a decent shot, though it could have been a step closer to the elbow.)

"I was just trying to get back to the middle of the floor," Tatum said of the game-winner. "My teammates and the coaching staff had confidence in me ... so that helped me out a lot. It's a great feeling. They put a lot of pressure on me to hit the shot, but I think that's what summer league is for, to learn some things if I would've made or missed it."

As for the Fultz connection that people will always will make with him (even in summer league), Tatum said he doesn't distract himself with it.

"Try to not pay attention to it as much as possible," Tatum said when asked how he'll deal with it. "Me and Markelle have known each other for a long time, from high school playing against each other, all the All-Star games, McDonald's, Hoops Summit, Jordan Brand. We finally reached our dream and I'm pretty sure we're going to compete against each other for a long time."

While Tatum's night was spectacular, it was last year's No. 3 pick who really carried the Celtics. Jaylen Brown looked like a man with NBA experience when he went for 29 points (10-for-16 shooting and 3-for-4 from 3-point range) and 13 rebounds.

Brown showed off this useful little move:

He murdered the rim with this two-hand slam:

He got downright silly with this video game spin move:

And he blocked Fultz's attempt at a game-winner just before the final horn sounded:

It goes to show how much a player can grow in one year.

Brown's 2016 Summer League Debut:
16 points (2-for-7), 6 rebounds, 2 assists, 2 blocks

Brown's 2016 Summer League Debut:
29 points (10-for-16), 13 rebounds, 0 assists, 1 blocks

Brown did commit a game-high seven turnovers, but overall he looked like a player who had grown out of the summer league.

"I just wanted to be aggressive and come out and just ultimately get better. I think that's the goal," Brown said. "Still got a lot to work on. But it was the first game and it wasn't bad."

The Celtics are back in action on Wednesday against the Spurs.

In:
• Boston Celtics
• Philadelphia 76ers
• NBA