Mar 5 NBA Action: Boston Celtics @ Golden State Warriors
Boston Celtics +8.5 @ GS Warriors
Oracle Arena, Oakland, California
March 5, 2019, 7:30 PM PST
We are backing the Celtics to cover the spread at the Warriors this evening, although with some trepidation, we must admit. One the one hand, Boston's slide over the last month is well documented. After a 35-19 SU run through February 5, the Celtics have since dropped six of their last ten, including three losses during this stretch as favorites of nine of more. Yet Boston is an OK 4-6 ATS overall during this stretch, and a profitable 2-1 ATS over this time from the position of as road dog. Thus, we are open to the potential that the implications of the Celts' recent performance letdown may be quite different for bettors than for Boston fans.
Supporting the idea of the road cover, we note that quality teams off near losses have been solid fades against all but the most familiar foes historically. The system of betting against teams with at least 65% win rates, off 1-4 point wins, against non-division opposition has been good for about a 7% return on investment (ROI) since 2005. This system is 38-17 ATS (69%) this season. Golden State overcame a 12-point half-time deficit Saturday to stave off the Sixers, triggering a play on Boston in today's contest.
Of interest, on a record of 101-82-6, this system's profitability is virtually unchanged in games played during the latter third of the regular season.
As an additional offset to our anxiety over Boston's near-term struggles, we note that the Warriors are not quite exhibiting the juggernaut-like form on display in recent years. To wit, exactly one week after Boston began to slip, the Warriors too seem to have hit a peak. Golden State has dropped four of their last seven out SU and are 1-10 ATS in their last 11 games.
Also in Boston's favor, back to 2013, the Celtics are 9-3 ATS versus the Warriors in head-to-head-play, including covers in each of the last five at Oracle Arena.
Separately, we note that Golden State sharpshooter, Klay Thompson, has been ruled out of today's action. As of the time of this writing, the line is down 1.5 points from its opening level of 8.5. By at least one quantitative technique, bookmakers may have under-reacted to this news.
ESPN's Real Plus Minus, for instance, attempts to measure the unique plus-minus impact of each NBA player by adjusting for the effects of each teammate and opposing player sharing the court. By this measure, Thompson's worth is -0.36 points per 100 offensive and defensive possessions, while presumed replacement player, Damion Lee sports an RPM of -2.05. Golden State's average number of possessions at home this year plus Boston's average number of possessions on the road suggest somewhere in the ballpark of 208 total possessions this evening. And, Thompson's average MPG of 34.4 suggest he is typically on the floor for about 71% of the Dubs' total possessions. Taking these numbers together, we estimate subbing Lee for Thompson costs Golden State about -2.5 spread points (if Lee inherits all of Thompson's vacated minutes).
[-2.05 - (-0.36)] x 209 x 71% = -2.51
Thus, inclined bettors that missed the Celtics at +8.5 might still consider +7.