The Case for Underdogs in Divisional Games

Before I get to my preview for tonight’s game between Arizona and San Francisco, I want to talk about a betting trend I’ve noticed this season. The reason why I want to talk about this trend is two-fold. First, it almost is certain to be worth your while from a financial point of view. And second, it has a direct application for tonight’s game.

The point is this: Against the spread, underdogs in games between divisional opponents are a gold mine. How do I know? Well, the results so far this year have been staggering. Underdogs in divisional games are 14-5-2 with the spread. Here is a recap:

• Week 1: Tampa Bay 31, Atlanta 24     TB +3 (win)
• Week 1: Kansas City 33, San Diego 27     SD +7 (win)
• Week 1: New York 20, Dallas 19     NYG +1 (push)
• Week 1: San Francisco 28, Los Angeles 0     SF +3 (win)
• Week 2: New York 37, Buffalo 31     NYJ +1.5 (loss)
• Week 2: Baltimore 25, Cleveland 20     CLE +7 (win)
• Week 2: New England 31, Miami 24     MIA +7 (loss)
• Week 2: Pittsburgh 24, Cincinnati 16     CIN +3 (loss)
• Week 2: Dallas 27, Washington 23     DAL +3 (win)
• Week 2: Los Angeles 9, Seattle 3     LA +7.5 (win)
• Week 2: Minnesota 17, Green Bay 14     MIN +2.5 (win)
• Week 3: Green Bay 34, Detroit 27     DET +7 (push)
• Week 3: Washington 29, New York 27     WSH +3.5 (win)
• Week 3: Seattle 37, San Francisco 18     SF +9 (loss)
• Week 3: Atlanta 45, New Orleans 32     ATL +3 (win)
• Week 4: Jacksonville 30, Indianapolis 27     JAC +3 (win)
• Week 4: Buffalo 16, New England 0     BUF +4.5 (win)
• Week 4: Atlanta 48, Carolina 33     ATL +3 (win)
• Week 4: Chicago 17, Detroit 14     DET +3 (win)
• Week 4: Houston 27, Tennessee 20     TEN +5 (loss)
• Week 4: Los Angeles 17, Arizona 13     LA +8 (win)

To be fair, it’s unlikely that underdogs continue to cover the spread at a 75% clip in divisional games. But that doesn’t mean these first four weeks were just a fluke. In 2015, underdogs in these situations went a combined 52-40-3 (.563), and in 2014 they went 54-41 (.568). In total, this means that the total over the last three years is 120-86-5, which is good for a 58% win percentage. Remember, to win money consistently when betting the spread, you need to hit close to 53% of the time.

More research is certainly necessary. I would like to take a look at the success of home underdogs specifically because they are 6-0 so far in 2016. Moreover, I’ve also noticed that underdogs of more than 7 points show some value in these rivalry games as well. I’ll continue to follow the success of underdogs in these situations; but with this in mind, I’d like to discuss tonight’s game…

vs 

Arizona Cardinals (1-3) vs San Francisco 49ers (1-3)

Spread: ARZ -3.5            Over/Under: 42

’16 DVOA: ARZ (10) > SF (31)

Public Betting: ARZ 68% 

In addition to everything I said above, why else do I like the 49ers tonight? For starters, Carson Palmer is out with a concussion, which means Arizona will turn to Drew Stanton. Unfortunately for the Cardinals, Stanton has been a mess of late. In his last three appearances dating back to last year, he’s had just a 39% completion percentage to go along with 0 touchdowns and 4 interceptions. That’s…not good. The defending NFC West champs also have some serious issues on their offensive line: They’ve allowed their quarterbacks to be sacked on 6.67% of dropbacks (22nd in NFL). Compare that figure to their 4.87% rate a year ago, which was 7th in the league and you can understand why the Cardinals offense has been sluggish.

In spite of all this, the Cardinals remain the heavy betting favorite. Are the 49ers that bad? Potentially, but I also know that they have lost to three quality opponents this year and own what an impressive blowout victory over the 3-1 Los Angeles Rams. Plus, I always believe it’s best to side with the House. Oh, and did I mention that this is a divisional contest?

San Francisco 23, Arizona 17 

*Best Bet: San Francisco +3.5 

Posted by Mando

Co-Founder of Check Down Sports. Die-hard Boston sports fan (Patriots, Celtics, Bruins, Red Sox -- in that order). Expert on all things related to the Super Bowl. Proudest life achievement: four-time fantasy baseball champion.