The Boston Celtics' season has been a tough one.
Despite sitting in the 2 seed in the Eastern Conference and winning 53 of their first 78 games, it wasn't exactly an easy go to get there.
The misfortune started with the season-ending injury to Gordon Hayward on the opening night of the 2017-18 NBA season, but the Celtics persevered, winning 19 of their first 23 games through November. Boston was also 30-10 entering the 2018 calendar year.
But the injuries kept coming. They lost Daniel Theis to a knee injury (a bigger deal than it may seem) and Marcus Smart to a thumb injury, and a slew of other key players have missed multiple games from other ailments and injuries.
Overcoming a Shane Larkin illness, though, is nothing compared to the loss of Kyrie Irving.
In the aftermath of left knee surgery, Boston Celtics All-Star guard Kyrie Irving will miss the rest of the regular season and playoffs, league sources told ESPN.
— Adrian Wojnarowski (@wojespn) April 5, 2018
Just how does that change their NBA title hopes?
Irving's Impact
By our nERD metric, which indicates expected wins over .500 a player would add to a team if he were a starter, Irving was the 12th-most impactful player in the NBA this season, with a nERD score of 11.2.
Boston's team nERD rating, which indicates expected winning percentage, of 59.5 ranked them fifth in the NBA. Our algorithms gave Boston a 7.1% chance to win the NBA Championship with Irving set to return.
With Irving on the court, the Celtics have maintained Four Factors marks of a 52.2-29.8, per NBAMath's FATS Calculator. They were comparable to the 2014-15 San Antonio Spurs, who lost in a seven-game series to the Los Angeles Clippers in the opening round that season in a loaded Western Conference.
With Irving off the court, they play like a team expected to go 42.0-40.0 over a full season, per the FATS Calculator. That's quite a dip.
Boston's Title Hopes Plummet
Boston's initial 7.1% NBA Championship chances ranked them fourth among all NBA teams, primarily because the Toronto Raptors' 71.1 nERD ranks the Raps significantly higher than the Celtics' 59.5 mark.
Despite a 3-game difference in the standings (56 wins for Toronto and 53 for Boston through 78 games), the Raptors have outscored opponents by 7.7 points per 100 possessions, compared to just 3.8 for Boston. That discrepancy in efficiency gave Toronto a 23.2% chance to win the NBA Finals prior to the Irving injury.
As for Boston, without Irving to return, their championship odds have dropped from 7.1% to 2.8%, according to our algorithm.
A surprise winner in all of this is the Philadelphia 76ers, whose odds jumped from 4.4% to 7.1%, thanks to a 61.3 nERD.