In a repeat of last year’s Eastern Conference Finals, we have the 4-seeded Cleveland Cavaliers squaring off with the 2-seeded Boston Celtics, starting with Game 1 on Sunday at 3:30 P.M. EST in Boston.

Since last year's meeting, to say a lot has changed would be an understatement.

Who are They Now?

First and foremost, Kyrie Irving was traded from the Cavaliers to the Celtics, but ultimately both teams got to this point without him, since Boston lost him to season-ending knee surgery at the end of March.

Other than that, both rosters have experienced a heck of a lot of turnover. The Cavaliers essentially flipped their whole roster at the trade deadline, while the Celtics made a bunch of moves to make room for Irving and Gordon Hayward during the offseason, only to be without them because of injury.

The Celtics have been the Cinderella story of this postseason, as they've gotten to this point while dealing with injuries to Irving and a slew of others, leaving only Al Horford, scary Terry Rozier and a bunch of young others. Along the way, the Brad Stevens-led C's won a series in which they were barely favored (against the 7-seeded Milwaukee Bucks), and another in which they were rare homecourt underdogs (against the 3-seeded Philadelphia 76ers).

In the meantime, the Cavs have been a tale of two teams: one that had to claw and scrape through seven games just to beat the 5-seed Indiana Pacers, and another one that flat-out embarrassed the 1-seed Toronto Raptors (who were favored) in a sweep.

Which version of the Cavs are we getting at this point? And when exactly do the Celtics turn back into an injury-riddled pumpkin?

The Algorithms vs. The Odds

Vegas has Cleveland at -290 to win the series (according to Bovada), which gives the Cavs an implied 74.36% chance to advance to the NBA Finals.

But while Vegas seems to have a bit of recency bias, suggesting that we’re getting the world-beater Cavaliers against a Celtics team whose magic is about to dry up, our metrics suggest that this might be a closer series than the experts think:

Cleveland is still favored at 66.85%, but we have the odds-on scenario being Cavs in six at 24.89%. This has the potential to be a longer, more hard-fought series than most people might realize. Don’t sleep on the fact that the Celtics had the league's number-one defense this year, and it’s not like Irving and Hayward had everything to do with that.

Speaking of Irving, it’s unfortunate that we’re being robbed of an Irving versus LeBron James showdown. If you’re wondering how Irving’s presence would have changed this series, we still would’ve had the Cavaliers to win, but only at 59.5%.

Either way, when the ball gets tossed up on Sunday, both teams will have to go with what they have. Which version of each team will show up?

Only time will tell, but don’t go counting out these Celtics just yet.