Steelers vs. Bills Week 1 NFL odds, spread: Ben Roethlisberger has been money as underdog; Josh Allen rarely loses as betting favorite

Something may have to give on Sunday in a matchup of 2020 AFC division champions when the Pittsburgh Steelers visit the Buffalo Bills, who are 6.5-point favorites on the Caesars Sportsbook NFL odds. Steelers quarterback Ben Roethlisberger has been fabulous in his career as a betting underdog, while Bills counterpart Josh Allen is almost invincible straight up as a favorite. In theory, both trends could continue Sunday.

One quick note: Steelers star linebacker TJ Watt, the +750 third-favorite at Caesars to win NFL Defensive Player of the Year (he finished second in 2020), will be a go after finally getting his huge contract extension Thursday. He had been with the team all through camp and the preseason to avoid fines, but was not practicing – i.e. "holding in" – until Wednesday.  

Watt agreed to a four-year, $112 million extension with $80 million in full guarantees. The average annual value of $28 million per season makes Watt the NFL's highest-paid defensive player. JJ's little brother is the better player now as TJ has double-digit sacks in each season beginning in 2018, recording 13, 14.5 and 15 sacks.

This likely will be the final season opener for Roethlisberger, widely expected to retire after this year. In the future Hall of Famer's career, he is 35-22-1 against the spread as a betting underdog and 31-27 straight up. This century, a total of 51 quarterbacks have started at least 40 games as an underdog and have a winning SU record:  Big Ben and Tom Brady.

Since Mike Tomlin became Steelers coach in 2007, his team is 38-21-3 ATS as a dog (not all with Big Ben, who has missed some games injured). That underdog cover percentage of 64.4 is No. 2 in the NFL among all teams since '07 behind the Patriots (67.7 percent).

It's the NFL debut of first-round rookie running back Najee Harris, who is a +1000 sixth-favorite to win NFL Offensive Rookie of the Year. The Steelers ranked last in the NFL in rushing yards last season and in yards per rush. That's very un-Steeler-like.

Meanwhile, since Allen was drafted in 2018, his cover percentage of 60 (27-18-2 ATS) is the best of any quarterback. He is 20-3 straight up as a betting favorite and an astonishing 11-0 as a favorite of at least five points.

Allen is 2-0 straight up and ATS in his career against the Steelers. Buffalo beat visiting Pittsburgh 26-15 in Week 14 last year. Allen had two TD passes. So did Big Ben, but he was picked twice and one was returned for a score late in the first half that totally changed the game. 

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