Reverse line movement in sports betting: How to tell where the public vs. sharp money is going – The Athletic

Sportsbooks are constantly adjusting and tinkering with odds and lines to balance betting markets. In an ideal world, they want the same amount of money on both sides of every bet so that they can take a little off the top and have no risk.

When one side of a bet is getting significantly more of the action, they are at risk to some losses. Sportsbooks dont like that. Thats why they move the line, to entice more betting on the other side and match up a potential vulnerability.

Thats the basics of line movement. Reverse line movement is a more advanced concept that occurs when a line moves against the trend of what side of a bet is receiving more action.

Lets take an NBA game with the Phoenix Suns at the Utah Jazz. The Jazz open as a 3.5-point favorite. Sports betting sites that show public betting numbers have the Suns getting nearly 80 percent of the action. That might be enough for a sportsbook to move the spread toward the Suns with a new line of Jazz -3. When it comes to line movement, theres a big difference between the percentage of tickets and the amount of money on each side, but for the sake of this example, both numbers are aligned and the line moves to Phoenix because of all the bets going to that side.

This is standard line movement. It wont raise any red flags but is a noteworthy trend in the betting action of this Suns-Jazz game.

Reverse line movement would come into play if the line moved to Utah -4 or -4.5. An overwhelming majority of the bets are already going to Phoenix and now the line moves to Utah, creating an even more enticing bet on the Suns for a majority of the betting public. What gives? Why would a sportsbook do such a crazy thing? What does the sportsbook or a small number of bettors know that the general public does not?

Now that weve established that reverse line movement is when a betting line moves away from the general betting public consensus we can get into why a sportsbook would want to do this.

The simplest answer is that a professional bettor, maybe even more than one, bet on the Jazz in this example. They saw something that most bettors did not. When those professional bettors, also known as sharps, make bets, sportsbooks take note. They need to know who is good enough to consistently take their money and respond accordingly. If a sportsbook respects a sharp bettor enough, they will move the line in that direction because the sportsbook wants to be on the same side as that bettor.

Its somewhat risky because the sportsbook will likely have even more action on Suns, putting them in a somewhat vulnerable position. This is the sportsbook essentially making its own value bet, thinking the sharp bettor is worth betting with and they will make more money moving the line this way.

This example assumes the line move toward Utah was actually reverse line movement from a sharp bettor. It could have been because of an injury update or weather conditions for an outdoor sport. The movement would also apply to the moneyline for the game because spread and moneyline bets are correlated. The concept works for sports where moneyline is more popular than spread (like baseball or soccer).

This part is easier to explain. Assuming its real reverse line movement based on a sharp bettor, which isnt always easy to prove definitively, wouldnt you want to be on the same side of a bet as a professional bettor? They dont win every bet, but that means its likely a good bet to place.

Once you see reverse line movement it might be too late. The line has to move for the reverse line movement to be apparent, meaning the edge is already smaller after the move is made. Its possible to still get the old line at a different sportsbook before they all react. Hunting for the old line at other books is the best way to take advantage of reverse line movement.

If the sharp bettor had a model that said the Jazz were six or seven points better than the Suns, they might be waiting for the line to move more toward Phoenix before placing their bet. As more and more action goes in the Suns direction, the line keeps moving and gets more appealing to the sharp bettor. Once they get a line where their model shows a significant enough difference between its prediction and the spread, the sharp bettor places the bet. Now the reverse line movement kicks in, to a line where the sharp bettor wasnt fully comfortable placing the bet. In this hypothetical scenario, theres still an edge compared to their model, but it isnt a significant edge.

Is that the bet you want? The sharp bettor didnt, waiting for an extra half or full point before placing the bet. This is why reverse line movement is significant to take note of, but may not always be actionable. If you can find the Jazz -3.5 elsewhere, matching what the sharp bettor got, go for it. That new -4 or -4.5 line isnt as appealing.

Reverse line movement is a cool trick for whenever it happens, but it requires watching public betting numbers to identify it and then finding a line that offers a good price before the move. If you read about reverse line movement in betting coverage of a game, its probably already too late.

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Reverse line movement in sports betting: How to tell where the public vs. sharp money is going - The Athletic