If you haven't heard of the zig-zag theory in the NBA playoffs before, it's exactly how it sounds: Bet against whatever just happened in the previous game. The Nets covered as an underdog? Bet the 76ers in Game 2.
But is that actually profitable? Thankfully, we can use our awesome tools at Bet Labs to quickly answer.
Is the Zig-Zag Theory Profitable?
The answer is no … kind of. Teams coming off a outright loss have covered the next game's spread just 50.2% of the time historically. Teams coming off an ATS loss have covered the next game at a 48.8% clip. Teams that lost both outright and against-the-spread covered in the next game at a 49.4% rate.
If you've blindly been following the zig-zag theory, you certainly haven't been a profitable NBA bettor.
That said, there are certain spots where it's been profitable. For example, home favorites coming off a loss and non-cover have historically been profitable, going 87-73-3 (54.4%) since 2004, good for a 6.2% Return on Investment.
That's a little misleading, though, as the market has largely adjusted to that lately. The value peaked in 2013, and it's slowly been losing value since. In 2016-17 these teams went just 1-9 ATS; last year they went an average 6-6.
Profitable Zig-Zag Trends
We can do better. These home favorites have returned a profit if they're undervalued by the public — getting 55% or fewer bets.
Those teams have covered the spread at a 59.8% rate, good for a 16.8% ROI. They've had a few poor seasons, but they've consistently returned a profit. That's a better trend line.
For what it's worth, the 76ers match this trend tonight.
There's a lot more to explore in Bet Labs with regards to the zig-zag theory. For example, higher seeds (1-3) have historically hit a 57.8% rate when playing as a home favorite after a loss and non-cover. They've been even better when coming off a loss in Game 2s.
When in Doubt, Follow Sharp Money
Of course, the betting market is quick-moving, and you can be sure that oddsmakers are very aware of the zig-zag theory and bettors' tendency to believe in that narrative. It's been much more profitable to follow sharp money, which we're always tracking both in our content and our tools like Bet Labs:
But don't stop there! Go test the tools out for yourself and find some profitable inefficiencies.