The last week of the NFL regular season is pro football’s Twilight Zone. Strange, hard-to-explain things happen.

“I don’t like Week 17, ever, because of who’s playing and who’s not playing. You get crazy swings in the point spreads. Some of them I was baffled by,” said Jeff Stoneback, director of trading for MGM Resorts.

DraftKings head of sportsbook operations Johnny Avello also found himself scratching his head over the bettors’ thinking on a few games. Among many games that saw huge point spread moves was Pittsburgh at Cleveland where the Browns, fighting for their first playoff spot in 18 years, were at home playing Pittsburgh. The Steelers’ playoff berth was secured and starting quarterback Ben Roethlisberger was being held out of the game.

The Browns started as 6.5-points favorites in NFL betting and soared to 10- to 10.5-point favorites.

“I thought the Browns number was way too high,” Avello said. “They’re not good enough to be laying 10 points to a Steelers team. Pittsburgh is not going to lay down, even without Ben (Roethlisberger). The Steelers are going to at least give an effort, and they did.”

Cleveland ended the franchise’s post-season drought pulling out a 24-22 win but didn’t come close to covering the spread.

The lines were influenced by the so-called sharps (professional bettors) who were handicapping factors that come up almost exclusively in Week 17, such as key players sitting out games entirely and speculation on starters being pulled early by teams who had little on the line.

Miami-Buffalo a Case in Point

Consider the Miami-at-Buffalo game where the Bills started out as much as 4-point favorites early in the week but were 3.5- to 4.5-point underdogs by kickoff perhaps on the belief that Buffalo quarterback Josh Allen would get pulled at halftime.

Miami also should have had more incentive; the Dolphins needed the win for a playoff spot. As it happened, Allen was replaced in the third quarter, but the Bills were in command by 22 points at the half on their way to a 56-26 win and the No. 2 seed in the AFC.

“I don’t know what the bettors were thinking there,” Avello said. “Buffalo still needed the game (for seeding) and it was at home for the Bills. So, I really didn’t understand the thinking on that (line) move.”

Stoneback was also mystified.

“The Bills-Dolphins game was crazy,” he said. Clearly the line move was all about bettors believing Allen would be yanked because, as Stoneback noted, “the first-half point spread was at pick and yet the (full game) was the Dolphins laying 3.5. As it turned out, the Bills came out in the second half and blew them out even more.”

At PointsBet, the wagering on Miami-Buffalo was mixed with 74% of the spread tickets on the Bills but 63% of the spread handle on the Dolphins.

Washington-Philadelphia Line Moves

And then there was the Washington-Philadelphia game where The Football Team needed the win to make the playoffs but an Eagles triumph would send the New York Giants to the postseason. The week started with the Eagles a slight favorite but by kickoff, the line moved to Washington as a 6.5-point favorite.

Leading up to the game, there were reports that the Eagles would send third-string QB Nate Sudfeld into the game at some point, and adding fuel to suspicions that Philly might have its own agenda when it issued a long list of starters who would miss the game. The Giants’ worst fears were realized as the Eagles pulled starting QB Jalen Hurts for Sudfeld to start the fourth quarter, sending the Twittersphere into outraged spasms that Philly was tanking the game.

In keeping with the day’s weirdness, Washington did win the game, 20-14, but failed to cover the final line. Still, plenty of bettors who got in their wagers at smaller spreads throughout the week cashed.

Moneyline Parlays More Popular

The Week 17 betting dynamics were made more convoluted by the fact that sharp money moved the line sometimes toward underdogs but public money stayed on the favorites. That was important for moneyline parlays and teasers. And in the end, that’s what rocked some of the books.

“The favorites were 13-2 straight-up (14-2 after Washington’s Sunday night win) so the moneyline parlays were a killer and the teasers were bad also,” Stoneback said. “Four big games (in the late day window) hurt us — the Packers (beating the Bears), the Cardinals (losing to the Rams), the Saints beating the Panthers, and the Buccaneers over the Falcons.”

What happened Sunday, Stoneback said, is that the betting public has developed an appetite for moneyline parlays so even if the favorites get beat on the spread, the public can still ride them to profitability by taking them to win straight-up in parlays.

“In the last couple of years, it seems the moneyline parlays have become more popular. Maybe it’s because people are more educated on what a moneyline is,” Stoneback said. “People are more confident in betting teams just to win so they figure they’ll bet three teams to win straight-up; they may not even have realized they could do that five years ago.

”We get a lot of $20,000 three-team money-line parlays that pay something like even-money, or maybe 3-to-2. So, it seems that people are willing to put up a lot of money on three or four large favorites and they have no problem laying that (odds) price in order to collect that ticket.”