When Caesars Sportsbook’s assistant director of trading Adam Pullen set the opening Super Bowl line at Rams -3.5, he thought the spread could’ve even been at the key number of -3.

That’s the line, Rams -3, he had set for a Super Bowl look-ahead spread before the conclusion of the AFC and NFC Championship games.

Despite his inclinations, however, the odds have gone in the opposite direction. As of Friday morning, the line sat at the market consensus of Rams -4.5.

“Personally, I don’t see the line moving any higher toward the Rams, but I didn’t think it’d move any higher than four,” Pullen said with a chuckle. “I don’t pretend to know everything. I’m not right all the time.”

It’s rather common for the market to move against even a bookmaker’s better instincts. While sportsbooks do set the initial line as they please, they’re privy to the same uncontrollable market factors that force odds movement in one direction or another.

In this case, it’s sharp action that did the trick. At certain books, Caesars included, sharp action is the single biggest determinant as to whether a line moves. On the same day Caesars opened Super Bowl odds at Rams -3.5, a $180,000 wager on Los Angeles to cover moved the line to Rams -4.

The difference between Rams -3 and Rams -4 is substantial. Betting veterans know this. Receiving more than a field-goal cushion in any game between two good teams is significant — but especially for a game such as the Super Bowl.

Since 2000, only two teams have covered as 4-point favorites or more. That’s an against-the-spread (ATS) record of 2-10-1. Favorites of three or fewer points, though, went 5-3 ATS over this time frame.

And after the line had already moved to a market consensus of Rams -4, a different bettor slapped down $522,000 on the Rams to cover. This bettor single-handedly moved the book’s line from Rams -4 to Rams -4.5, and much of the rest of the market followed.

Both of these big-moneyed bettors had previously been flagged by Caesars as a sharp bettors. Caesars identifies sharp bettors as those who make large cash wagers and have historically netted closing line value on those bets.

(You obtain closing line value — CLV — if you place a bet that improves before the start of a game. For instance, if you took the Rams at -3.5 and the line closes at Rams -4.5, then you would have received closing line value because you beat the closing odds by a point.)

Other books move their lines with different considerations in mind. At PointsBet, they give the global market more weight, said Mike Korn, a sports analyst at the company. That means if several other sportsbooks make changes to their lines, regardless of PointsBet’s liabilities or sharp action, they’re more likely to make alterations, too.

There doesn’t appear to be enough momentum to shift this line down toward the key number of Rams -3. Or even below Rams -4. Even a substantial shift in public sentiment won’t be enough to move this line that low — only the massive moneyed bets of a dozen or so Cincinnati backers will.

If you’re hoping for better value on the Rams spread, it doesn’t hurt that “Mattress Mack” — Houston furniture magnate Jim McIngvale — put in the biggest mobile wager of all-time on Thursday night ($4.5 million at +170 at Caesars Sportsbook) on the Bengals’ moneyline.