Why you should pump the brakes on betting home underdogs

Let's start with the stat to end all stats: 1,859-1,860-111.

That's the against the spread record of all NFL favorites over the last 15 NFL regular seasons, as mentioned by David Payne Purdum of ESPN. Be more spot-on, you can't. And for good measure, 1,890 games have gone over the total, 1,886 have gone under, and 64 landed on the number.

No, Vegas doesn't know - but the oddsmakers do, and it's a testament to how difficult it is to find an edge when capping NFL games. There's a reason we constantly model, crunch numbers, weigh the market, and dig for any advantage we can to net wins.

This season, there's one edge in particular that's been profitable, and it's one that squares and sharps alike have noticed: Home underdogs have been on a fantastic run to start 2018, going 16-6 (72.7 percent) against the spread through the first five weeks of the season. The trend started gaining traction in Week 5 when all four home 'dogs covered while three won straight up.

I know what you're thinking. But please, pump the brakes. For a couple of reasons, it's far from ideal to start blindly submitting tickets on home teams catching points.

For starters, this is a painfully small sample size. We've gone in depth on trends and how they take out the predictive aspect, telling us what has happened rather than what will and completely ignoring both the present numbers and the market.

Given how much steam the trend has picked up, bettors are bound to react, or even overreact. There was a good point brought up in gambling circles last week that the market was already showing signs of overreacting this season, in that more common, square bettors are shifting to becoming more contrarian bettors - fading the public - without any real reason to do so. Betting on the home underdog just to bet on them might actually start opening up edges on the road team when all the value has been wrung dry on the home side heading forward.

Given the balance of the league, most road favorites will likely toe the line of key numbers in the 3-4 range, where the smallest of line movement can swing the value of a play. We've witnessed how the market has shaped numbers and how it's affected getting the best number, with a couple of different scenarios already this season.

For example, on Monday Night Football in Week 4, the undefeated Kansas City Chiefs opened up as four-point road favorites over the Denver Broncos. The line bumped all the way up to -5 before money came in on Denver, pushing the closing number down to -3.5. If you didn't think to get even a half-point wasn't crucial in the NFL, ask those who took the Broncos at 3.5 as Kansas City went on to win by four.

Case in point: Don't be surprised to see home underdogs become a trendy pick, prompting drastic line movement and adding value to the road team.

Lastly, take another look at the stat at the top. You can bet that favorites - or underdogs - have gone on some crazy streaks in the past over similar, smaller sample sizes. The oddsmakers are so precise that the 16-6 clip is likely to revert back to the mean sooner than later.

And if you have any doubts, here's some food for thought: According to TeamRankings.com, home underdogs went 47-47-4 last season, 211-211-12 the last five, and 413-434-25 the last 25.

Again, absolutely dead on.

Edges in this market don't last long. And if you're looking to hop on the home 'dog bandwagon, you had better jump right back off.

Copyright (C) 2018 Score Media Ventures Inc. All rights reserved. Certain content reproduced under license.