The Boston Celtics open up the NBA Playoffs on Sunday afternoon against the Philadelphia 76ers at TD Garden (1 p.m. ET).

With the No. 2 seed in hand and duo of Jayson Tatum and Jaylen Brown healthy, the Celtics look primed to make another run at the NBA Finals, where they have already been twice in the last four years.

The Celtics lost against Golden State Warriors in 2021-22 before winning the title against the Dallas Mavericks in 2023-24. 

While there's plenty of reasons for optimism for Joe Mazzulla's team, there are some things to be wary of, so let's dive into the biggest worries for Boston.

With Brown, Tatum, Payton Pritchard, Sam Hauser, Derrick White and Nikola Vucevic, the Celtics are plenty capable of lighting up the three-point line. However, they are also completely dependent on it, meaning if the shots aren't falling, they could have a hard time winning.

Boston attempted the fourth-most three-pointers per game this past season (42.1), and they made the third-most (15.5). Playoff defense is a different beast: The offense won't be able to flow as easily and the shots won't be as open.

Can Boston hit tougher and more contested threes? Can they use their offensive scheme to create those same open looks they got in the regular season, even against those tougher defenses?

That remains to be seen.

If the defenses are choking off the three-point line, how will the Celtics respond? Well, my first answer is that they should try to get to the lane and get to the foul line.

Two problems: Playoff games don't come with as many foul calls, making that a harder strategy, and it's not really in the Celtics' DNA anyways.

Boston attempted just 18.7 free-throws per game this season - the fewest in the league. They made just 15.1, which was good for 29th in the league. 

As stated above: They are truly dependent on the three-point shot, and if it's not falling, there aren't real answers available to them.

Vucevic broke his finger in early March and returned to mixed results at the end of the season. Can he provide Boston with valuable minutes, solid passing and good shooting from the outside? And how about Luka Garza, who has shown ability as well: Can he perform in the playoffs?

That all remains to be seen as well.

Tip-off time is 1 p.m. ET. The game will air on ABC.

Remember to join our CELTICS on ROUNDTABLE community, which is FREE! You can post your own thoughts, in text or video form, and you can engage with our Roundtable staff, as well as other Celtics fans. If prompted to download the Roundtable APP, that's free too!