The Boston Celtics are out to a great start in the NBA Playoffs.

The C's, who went 56-26 in the regular season to earn the No. 2 seed in the Eastern Conference, beat the Philadelphia 76ers 123-91 on Sunday afternoon at TD Garden.

Boston leads the best-of-seven 1-0 with Game 2 to come on Tuesday night.

Here's what you need to know.

After tearing his Achilles in the Eastern Conference semifinals last season, Tatum was back on the floor in the postseason. He scored 25 points on 9-of-17 shooting, while also pulling down 11 rebounds and dishing out seven assists.

Speaking with ESPN after the game, Tatum said he was relaxed, excited and grateful for the opportunity to be back in the playoffs. 

The Celtics and their fans were grateful to have him as well. Tatum made all kinds of history in this performance, including becoming the third NBA player in the play-by-play era to reach those numbers (21 pts, 8 rebounds, 4 assists, 2 steals) in the first half of a playoff game, joining Jimmy Butler (5/27/22) and Russell Westbrook (4/19/17). That came from Celtics Stats.

--It wasn't just Tatum who excelled in this one, as six total Celtics registered double figures. Jaylen Brown (26), Neemias Queta (13), Payton Pritchard (12), Sam Hauser (12) and Derrick White (10) all chipped in.

--Tyrese Maxey led the way with 21 points for Philly, but it was a difficult 21 against Boston's defense. Maxey was just 8-of-20 from the floor and 1-of-4 from three-point range.

--The Celtics out-rebounded the 76ers by three, while also registering 11 more assists (31 vs. 20).

--The Celtics committed only eight turnovers while Philadelphia had 14.

The Celtics, who have been heavily reliant on the three-point shot all season, were again on Sunday. They connected for 16 three's in the win on 44 attempts.

Contrast that with the 76ers, who were just 4-of-23. 

We questioned if the Celtics were too reliant on the three and if they weren't able to get to the foul line enough. Well, they did on Sunday, shooting 22 free-throws. Philadelphia shot 23, but the Celtics will take a near-even deadlock.

76ers star Joel Embiid did not play in this contest because of an emergency appendectomy that he underwent on April 9. It's unclear if he'll be available at all in this series, but the 76ers could certainly use him if they want to make this series competitive moving forward.

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