The Boston Celtics lost their final game before the All-Star break, their first time tasting defeat in 10 games. The hot stretch has seen the Boston Celtics’ odds to win the NBA title shorten considerably. FiveThirtyEight has even gone so far as to make them title favorites.
During the past calendar year, we’ve seen the Atlanta Braves storm back from long in-season odds to win the MLB championship. The Bengals nearly did the same thing in the NFL after being as high as 150-to-1.
Could the Boston Celtics be the latest longshot team to win or at least challenge for a title?
How Long Did Boston Celtics Odds Get?
Languishing around .500 in January, they found themselves falling down the boards. They could be found at +15000 (150-to-1 odds) around this time.
People often say “life comes at you fast” when things turn for the negative, but the same thing applies here in reverse for the Celtics. Only a month later and 12 or so games later, they’re now around consensus odds of +2500.
That’s a jump from 0.66% title chances (not vig-adjusted) to just under 4%. That might not seem like anything to write home about, but it’s a pretty massive jump. It’s the difference between a team we aren’t even discussing as a distant contender to a team with legitimate title hopes.
So, how much should we believe in the Boston Celtics’ championship odds? Let’s look at the cases for and against them.
The Case For The Boston Celtics
Start with this eyebrow-raising fact: the FiveThirtyEight model has the Boston Celtics as the NBA championship favorites. They estimate their chances of winning the title as 21%. That’s 3% clear of the next-strongest team, Phoenix. According to FiveThirtyEight, Boston should be around +375, a mile off the market best price of .
FiveThirtyEight has (somewhat infamously) not been afraid to publish some wildly off-market opinions. Sometimes, they make themselves easy to laugh at, like when they tabbed Golden State as a sub-.500 team with basically zero shot at winning the title this preseason. But, those same predictions correctly foretold the demise of the Lakers when the market had them ranked as an elite contender.
So, why might the model be so high on Boston?
Well, they have organized themselves into an elite defense, for starters.
Boston’s Elite Defense
Bringing a roster heavy on size and length, with defensive-minded big men, everyone figured defense would be Boston’s calling card. That has finally come to fruition in recent weeks.
Allowing 102.7 points per 100 possessions, Boston has closed in on Golden State for the top efficiency number in the league. The starting five is even more fierce. As ESPN’s Zach Lowe recently wrote ($), that group allows an anemic 88.8 points per 100 possessions.
No team allows a lower eFG%, and only one has allowed fewer shots at the rim, according to Cleaning The Glass.
Sometimes, teams that wall off the lane can do so at the expense of defensive aggression. Not so for Boston, which also ranks ninth in turnover rate. They still put a ton of pressure on the opponent.
And one injury won’t sink this defense the way Rudy Gobert going down would torpedo the Jazz. Boston’s top player in the Defensive Player of the Year market at DraftKings Sportsbook (Robert Williams III) checks in at seventh on the board. One can see that balance with the FiveThirtyEight player ratings system, which tabs all six of their top players in terms of minutes as large defensive positives.
Built For Playoffs
Matchups rule in the playoffs. Opponents make micro-adjustments that target your weakest point on defense, a ruthless strategy most notably employed by LeBron James in recent years. They’ll tilt their defensive help away from your least threatening players, much more so than they will in the regular season.
Boston’s balanced roster figures to make that difficult. They can play multiple systems and switch ball screens if needed with big men who can move and wings and guards who have size and strength. On offense, their entire top eight in minutes is above their positional median in points per shot attempt with the exception of Al Horford, per Cleaning The Glass.
In Jayson Tatum and Jaylen Brown, they have the big wings that dominate playoff basketball as their team centerpieces.
Winning Despite Bad Luck
Even with the recent surge that has Boston at a respectable 34-26, the team has still underperformed in terms of its record. That is, they’d have several more wins with neutral luck, which would have them in prime contention for the top seed.
Boston’s differential of +5.4 points per game is the best in the East by a pretty wide margin (second: Miami, +4.5).
Cleaning The Glass has them at the fourth-unluckiest team, 5.6 wins below where their differential “should” place them. Bumping them from 34 to 40 wins would have them tops in the East by two games.
ShotQuality, which bases its numbers on the quality of a team’s looks and the ones it gives up, estimates Boston should be 38-22, which would tie them for the East lead. Their numbers have Boston as ninth-unluckiest team.
The Case Against The Boston Celtics
Of course, if the article ended there, we would just suggest you got bet Boston to win the title and scoop that easy value.
However, it’s not that simple. While the Celtics have their strengths, there’s a reason the market has moved them to +3000 and not closer to +300 like FiveThirtyEight estimates they deserve.
Boston’s Offense Kind Of Stinks
Given Boston’s awesome defense, one might wonder how they’re chilling in the sixth spot in the East. The answer largely lies in a subpar offense.
Generally speaking, conventional NBA wisdom says you need to be top 10 or close in both offense and defense to truly contend for the title. Otherwise, you will likely run into an opponent that can exploit one of these weaknesses and vanquish you.
Boston has the 18th-ranked offense according to Cleaning The Glass. Simply put, there’s no recent precedent for a team with an offense this bad winning the championship.
CTG’s numbers go back to 2003-04. The worst-ranked offense to win the title was that year’s Pistons at 13th. Frankly, basketball looked totally different back then. Every other champ landed in the top 10.
We mentioned earlier that Brown and Tatum are exactly the sorts of big wings that have dominated in the playoffs dating to Michael Jordan’s days with the Bulls. But, they score 113.6 and 111.8 points per shot attempt, respectively. Those are solid numbers but pale in comparison to the likes of recent championship centerpieces like Kevin Durant, Giannis Antetokounmpo and LeBron James.
Tatum’s scoring late in the clutch has been particularly scattershot and a reason for their demise as favorites against the Heat in the bubble. Among high-usage players in the clutch (>25%) with more than 20 games played this season, Tatum ranks 22nd of 28 in true shooting percentage. He’s third from the bottom in both turnover rate and assist percentage.
Does this team have a reliable way to get a bucket at the end of games?
The Path Will Be Difficult
While the West boasts the two title favorites in Phoenix and Golden State, the East has the next four teams in the markets and six of the next eight, counting Boston.
Most likely, all five of the other six top East teams would be favored over Boston with the only possible exception being Chicago. Currently, Boston occupies the No. 6 seed, which means they would likely give up home-field advantage in every series.
Even if FiveThirtyEight’s projections prove true and Boston ascends to the No. 3 seed, they’d be favored in only their first-round series against someone like the Cavs or Raptors. Then, they’d be sizable underdogs against the top dogs like the 76ers, Heat, Bucks and Nets.
They’d also be decent-sized finals underdogs against the Suns or Warriors.
Plugging some very rough guesses on prices for these potential series into a parlay calculator (-250, +150, +180, +230) yields a price around +3000. That’s in line with the market, indicating influential bettors have hammered the value out of the Boston Celtics’ odds.
Maybe They’ve Gotten Lucky As Well?
We laid out the case for an unlucky Boston Celtics team earlier. But, the luck metrics don’t all paint the same picture of an unlucky team due for some positive regression.
Cleaning The Glass has Boston’s “3-point defense” — ratio of opponent makes — fourth-best in the league. We put that in quotes because it can be a very noisy stat, subject more to the whims of fate than actual ability. Boston also ranks tops in opponent shooting on long 2s.
According to Lowe’s reporting, Second Spectrum tracking data has Boston as the single biggest beneficiary in the league in terms of opponents underperforming their expected effective field goal percentage based on shot location and nearest defenders.
Maybe their defense reflects as much good luck as great performance.
Buy High Or Sell High On Boston Celtics?
If you believe in the projections, then the Boston Celtics are still undervalued in futures markets. While the price has shortened hugely, +3000 is still a fantastic return even if you believe Boston is merely a top-10 sort of team and not the league’s best like FiveThirtyEight.
As for unbelievers, while you might have a tough time finding a two-way championship market and laying massive juice against a Boston title run, you can still fade this team. Obviously, you can go game to game, but you could also take under wins in the in-season markets.
Whatever side you like in Boston Celtics odds, there’s no doubt it represents one of the more fascinating futures cases. They’ll be an interesting team to track as the league moves into the “second half” (most teams are about two-thirds through their seasons) and closer to the NBA finals.