Football Betting: Key Numbers and Off-Standard Lines

I had planned on giving a detailed breakdown of Week 1 NFL action this week and talking about key numbers next week, but a handful of phone calls yesterday changed my mind. We had a few newer players who were a little puzzled because their wager on the Patriots was +3 -120. In fact, one player wanted to close his account because our lines were weird. Since I currently see off-standard odds on eight of next week’s games at different books, including next Monday’s game, I figure this is a perfect time to cover key numbers and off-standard lines. Again, I have borrowed from a column I wrote last football season, but it warrants repeating.

First off, football is unique among the major pro sports in terms of how points are scored. In baseball, hockey and soccer, all scores are valued as a single point. These sports also tend to have low scores and the average margin of victory is extremely low so pointspreads aren’t used in the same way as they are in football and basketball, and moneylines are the most common form of betting. Basketball scores come in increments of 1, 2 or 3, but the high amount of scoring makes for an even distribution of final scores. As a result, basketball is perhaps the simplest sport to wager on in terms of lines offered. Football gets complicated because the scoring comes in chunks of 3 points (for a Field Goal) and 7 points (for a converted Touchdown). There is also a small amount of other scoring possibilities with safeties providing 2 points, missed extra points making a Touchdown worth only 6 and the two point conversion making 8 a possibility. Scoring in football tends to take place in football on average only about 8 times a game so, unlike basketball, the final scores do group around certain numbers, known as key numbers. The major key numbers are 3 and 7, but 1, 4, 6, 10, 13 and 14 have a high likelihood of being the final margin of victory as well and are sometimes referred to as minor key numbers. If we look at how all these numbers relate to 3 and 7, its easy to see why they occur frequently. The following chart shows the frequency of certain final scores for the 2001 NFL season as well as the relationship of the number to a combination of Touchdowns and Field Goals:

  • 3 17.3% Field Goal
  • 7 9.7% Touchdown
  • 10 6.9% Touchdown + Field Goal
  • 4 5.6% Touchdown – Field Goal
  • 1 4.4% Touchdown – 2 Field Goals
  • 6 4.4% 2 Field Goals
  • 14 4.4% 2 Touchdowns
  • 13 4.0% Touchdown + 2 Field Goals

This past weekend had 5 games decided by a Field Goal and 2 more won on special teams Touchdowns in Overtime so it was very possible that just just 3 points could have decided 7 of the 16 games. It is easy to see that a Field Goal is the difference in a lot of NFL games. I’m sure that this is not a big surprise to you but lets look at this from a sportsbook’s point of view.

Lets use Monday Night’s Pittsburgh-New England game to illustrate the danger to the House and what sportsbooks must to do to avoid the peril. The line in this case opened at Pittsburgh -1 several weeks back and was quickly bet to -2.5. Here is where the Book Manager’s nightmare begins. At -2.5 bettors loved the Steelers but as soon as the House moved to -3, the action shifted to New England. If 3 weren’t a key number, this would have been no problem, as book managers would simply move between the two numbers to balance action. Unfortunately, because the spread was -3, moving between 2.5 and 3 entails large risks. I covered this a little bit in Issue #22 and I will talk more in a later column, but here is a quick recap.

In the most basic of cases, lets assume there were wagers of $110 to win $100 on the Steelers -2.5 and then $110 to win $100 on Patriots +3. The game is balanced but the House would risk being sided if the game ended with the Steelers up 3. The Pittsburgh wagers would win but the Patriots wagers would push so the House would lose the $100. In this case, the House would be in a situation where it could only lose $100 or collect the vig of $10 if the score fell on any other number.

The chance of the final score for a game landing on 3 is roughly 17% as we saw above. Assuming an even split between dogs and favorites, the chance of a 3 point favorite winning by 3 is about 8.5%. This would mean that 8.5% of these games would result in the House being sided or middled. This would be disastrous for a business where 4.5% is the profit margin! Now lets look at what sportsbooks do to balance action without moving on or off key numbers.

There are two ways a sportsbook can avoid the risk of key numbers. The first way is to know what the closing line will be and to get to it as soon as possible. For example, the Rams game this weekend opened at St. Louis -2.5 and early action was on the Rams. Bodog’s top bookmaker, Kent, predicted an ultimate move to -3 and moved the line there as quickly as possible. The Rams money continued at -3 so this ended up being the right move. Unfortunately, this is very difficult to predict and mistakes can be costly.

The other way to balance action is to alter the odds associated with the pointspread. Most pointspreads are offered at standard odds of -110, meaning you must risk $110 to win $100. (Remember that when sportsbooks move a pointspread, the odds don’t change, as the spreads only affects whether your wager is a winner or not. Changing the odds, on the other hand, doesn’t affect whether your wager is a winner or not, but instead affects the payout.) By changing the odds away from the standard of -110, the House can make the same line more or less attractive to people looking to place wagers. The Pittsburgh-New England line had plenty of this. Bettors liked the Steelers -2.5 and also liked the Patriots +3 so a middle ground is the bookmaker’s only choice. In this case, the line was -2.5 (-120) at some books and -3 (Even) at others. Bettors now had a choice, they could take Pittsburgh at only -2.5 but would have to risk $120 to win $100 or they could lay -3 but lay only $100 to win $100. The -3 spread is far more likely to be a push but the payoff is better. New England bettors could now get +3 instead of +2.5 but would have to risk $120 instead of $100 to win $100. Off-standard lines split the bettors into the two groups (those that like the extra half point and those that like laying the lower price) and give books a chance to balance action without having to move on-and-off a spread such as -3.

I checked 20 books yesterday and found off-standard lines at 18 of them for the Monday Night game so this is far more common in the NFL than many new bettors think it is. As it turned out the score was never close and books breathed a sigh of relief with the Patriots winning by 16. Hopefully now when you see a sportsbook offer a line that is off-standard, you will know the logic behind it and hopefully you can benefit by looking for some value and laying less than -110 on the team you want. This also explains why many books charge premiums for buying points on or off key numbers.

Now I’d like to introduce a new feature to my column – Kent’s Line Move of the Week. He is Bodog’s number one bookmaker and I have asked him to talk about an interesting line each week of the football season. This week’s line was the Stanford-Boston College line that opened at the very first books at BC -6/-6.5 and closed all the way up to -11. The game of course ended 34-27 for Boston College after the Eagles scored 17 unanswered points in the fourth quarter including a TD with just over 30-second to go in the game. Bettors who got in early cashed winners with Boston College, those betting later pushed, and others jumping on the steam move ended up with losing tickets. This was a good lesson in playing favorites early and dogs late – if you did both of these things on this one game you would have cashed a ticket on both sides for an easy middle. It was also a lesson in why players cannot simply follow the steam plays and come up with winners – following steam action means you are always getting the worst of the number. The bettors are what make the line move so if you don’t get it early then getting the worst of the line will always catch up with you if you choose to simply follow.

As always, feel free to email if you have any questions or comments. My thanks to Kent and I will be back next week with a detailed analysis of a week’s worth of line moves. I’d also like to take this opportunity to pass along my thoughts and prayers to those effected by the tragedy of a year ago.

The enjoyment of your wagering experience with us is my number one priority. Should you have any questions, concerns, or comments, I will personally ensure you are satisfied with your Bodog experience.

Good luck with your wagers!

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Rob Gillespie is President of Bodog Sportsbook & Casino