No NBA team has ever finished the playoffs unbeaten. Might the Golden State Warriors make history this year?
At 12-0, the Warriors are already off to the best start ever to a postseason. They joined the 1989 and 2001 Los Angeles Lakers as the third team to sweep its way to the NBA Finals since the playoffs expanded to 16 teams in 1984. However, both of those Lakers teams played just 11 games against Western Conference foes because the first round did not go from best-of-five to best-of-seven until 2003.
Both those Lakers teams lost Game 1 of the NBA Finals. After losing starting guards Magic Johnson and Byron Scott to hamstring injuries, the 1989 Lakers were swept by the Detroit Pistons. The 2001 Lakers, meanwhile, won the next four games after losing Game 1 to the Philadelphia 76ers to finish 15-1 -- the best record in playoff history ... so far.
Golden State has a chance to surpass the 2001 Lakers. To get there, the Warriors will have to beat their toughest competition yet, the defending champion Cleveland Cavaliers.
How much better will the competition get?
There's no question that Golden State's undefeated run to the Finals benefited from injuries to opposing players. Starters Jusuf Nurkic (Portland Trail Blazers) and George Hill (Utah Jazz) missed three games during their teams' four-game sweeps at the hands of the Warriors, as did All-NBA First Team pick Kawhi Leonard of the San Antonio Spurs.
We can estimate the talent of the rosters the Warriors actually faced using minutes played in the series and the multiyear, predictive version of ESPN's real plus-minus (RPM). This method suggests that the toughest West team Golden State played (factoring in health) was actually the Utah Jazz, who rated about 3.2 points per 100 possessions better than an average team -- similar to the Boston Celtics during the regular season (plus-3.1 net rating).
The Warriors beat the Jazz by 16.5 points per 100 possessions in their sweep, suggesting they were playing at a level 19.7 points per 100 better than average.
Meanwhile, RPM suggests that the Cavaliers -- who also saw All-Stars Kyle Lowry and Isaiah Thomas miss large portions of their respective series against Cleveland -- faced an even weaker group of opponents in the Eastern Conference.
Overall, this method suggests the Cavaliers have played 17.9 points per 100 possessions better than league average during the playoffs.
Clearly, neither team faced any opponent as strong as the other team on the way to the Finals. Based on minutes played so far in the postseason, RPM estimates Cleveland has the talent of a team with a plus-7.0 net rating -- more than twice as good as the Jazz -- while Golden State is at plus-11.1. And remember, that's with both teams playing deep reserves extended minutes during garbage time.
Realistic rotations for this series push the Cavaliers to plus-7.8 talent and the Warriors all the way to plus-14.0.
What are Golden State's chances of sweeping the Finals?
If RPM is accurately rating the two teams, a sweep is a reasonable outcome. Based on those projections, Golden State would be expected to win in four games about 20 percent of matchups and win the series 88 percent of the time.
Bettors are understandably more conservative given how well Cleveland has played in the postseason. The latest projections from market-based PredictWise find an implied probability of 72 percent for the Warriors to win the Finals.
Based on that and the typical home-court advantage used by linesmakers (about 3.5 points), Golden State would have about a 69 percent chance of winning at home and a 46 percent chance of winning on the road. Multiplying that out suggests a 10 percent chance of a sweep.
It's worth noting that the series odds price in the chance of an injury or other unforeseen event that would alter the series in favor of the underdog. The line for Game 1 suggests that bettors are somewhat more optimistic about the Warriors' chances at full strength.
The money-line odds for Game 1 imply a 74 percent chance of Golden State winning at home, which would mean the Warriors are probably marginal favorites in Games 3 and 4 at Quicken Loans Arena (52 percent chance of winning). Based on those probabilities, Golden State would be expected to sweep the series about 15 percent of the time.
Together, the three different methods of estimating the Warriors' chances of sweeping the series probably give a good reasonable range. They enter the series with something between a 10 and 20 percent chance of finishing the playoffs unbeaten, with the middle of that range -- 15 percent -- as the most realistic expectation.
Golden State can also make history by winning the series in five games. That would give the Warriors the best record (16-1) in playoff history, just ahead of the 2001 Lakers, who finished 15-1. Similar analysis suggests Golden State has somewhere around a 25-30 percent chance of winning in five games.
Add that to the chances of sweeping and the Warriors have between one in three and one in two chances of the best record in playoff history. We'll find out soon whether the Cavaliers are good enough to prevent that from happening.