Which team has the NBA's best core (and why is it the Boston Celtics ?) ESPN senior reporter Tim Bontemps recently took some time to put together a ranking of the best three-man cores in the league right now, with an eye to their future potential impact.

The Celtics will close out NBA Cup group play this Friday in Chicago. Here’s how they can book a spot in the knockout rounds.

In the league's Eastern Conference, the Cleveland Cavaliers have been the only other team that looks like a genuine contender. And out in the Western Conference, the race is a bit more pitched with the Oklahoma City Thunder, Golden State Warriors, and even the Los Angeles Lakers hinting that they might be in the mix to hang a banner this summer.