A betting line is a forecast that keeps updating. Between the open and the start, the price on one side can travel dozens of cents as news breaks, money arrives and books raise their limits. To a casual bettor that is noise. To a disciplined one it is one of the most useful signals on the board: it shows where the market thinks the fair price is heading, and it opens short windows where one book has not caught up with the rest.
Guru-frat reads every move against Pinnacle, the sharpest market we track and the source of every no-vig fair price on the site.
Why prices move
A book moves a price because it learned something, or because it holds more risk on one side than it wants. Both come from a handful of places.
- News. Injuries, confirmed lineups, a scratched starting pitcher, a goalie change, weather. The fastest moves follow news, and books often suspend the market while they reprice (see locked markets).
- Sharp money. Some bettors beat the closing price over thousands of bets, and the books know who they are. A market maker like Pinnacle, which takes big bets from winning players on a thin margin, moves when that money arrives, and the rest of the market reads the move as information.
- Public money. Recreational bettors tend to back the teams they know and the games they watch. When that volume piles onto one side, a soft book may shade that side to a worse price instead of moving the whole market.
- Limits rising toward the start. Openers go up with low limits because the book is least sure of them. As kickoff approaches, limits rise, more money tests the number and the price gets harder to beat. That is why the close is the benchmark for closing line value.
- Copying. Many books take their cue from the market makers instead of pricing every game from scratch. The lag between the two is where stale prices come from.
Reading a 72-hour chart
Here is the Raiders ML line from Chiefs vs Raiders (NFL, kickoff Sun 4:25 PM ET), sampled every three hours at all four books. The chart plots implied probability instead of the price, so every book shares one scale. Higher on the chart means a shorter price: the market rates the Raiders as more likely to win.
- PIN Pinnacle +173 −23¢ open +196
- DK DraftKings +168 −22¢ open +190
- FD FanDuel +176 −14¢ open +190
- MGM BetMGM +199 +9¢ open +190 · best
- Fair +180 −24¢ open +204
Pinnacle opened the Raiders at +196 on Thursday and deals +173 now, a −23¢ move. Its no-vig fair price went from +204 to +180: the market now gives the Raiders 35.8% instead of 32.9%. DraftKings and FanDuel moved with it (−22¢ and −14¢). BetMGM went the other way, to +199 (+9¢). The green gap at the right edge, between the fair line and BetMGM +199, is this game’s edge.
Steam moves
Most movement is gradual, a few cents at a time as the price absorbs bets. Steam is the opposite: a sudden, sizable move at the sharpest book, the footprint of money or news the market respects. Guru-frat’s rule is mechanical.
The cents scale is linear and joins at even money, so a move across it counts the way it should: +105 to −105 is 10¢, not 210. And only Pinnacle counts. A soft book jumping 10¢ is usually catching up with a move that already happened; Pinnacle jumping 10¢ is the move.
Stale prices: where +EV windows come from
After steam, the other books decide whether to follow. Often they do, within a minute or two. A book that does not, or that moves the other way to balance its own customers’ bets, is left dealing a price the market has already moved past. For as long as that lasts, its number pays more than the new fair price, and the same EV formula that grades every play turns an ordinary line into an edge.
BetMGM is the only book still paying more than fair, and the window has been open for 6 minutes. It did not just stand still: in the last three hours it went the other way, from +180 to +199 (+19¢), while Pinnacle steamed from +185 to +173. The edge is the gap between +199 and the new fair price, and it closes the moment BetMGM catches up.
Of the 10 steam moves on the board right now, 4 left a soft book paying more than 2% over fair (EV above +2%), the line Guru-frat uses to call a price stale. In 4 more, the best soft price still beats fair, but by 2% or less. In the other 2, no soft book pays more than fair. The 6 most recent:
| Game | Pinnacle | Best soft book now |
|---|---|---|
| Padres vs BrewersMLB · Padres ML · 2 min ago | +130 → +118−12¢ in 4 min | DK+140S+7.5%Stale price |
| Flames vs KrakenNHL · Kraken ML · 2 min ago | −132 → −147−15¢ in 2 min | MGM−132C+2.1%Stale price |
| Chiefs vs RaidersNFL · Raiders ML · 3 min ago | +185 → +173−12¢ in 4 min | MGM+199S+7.0%Stale price |
| Cowboys vs TexansNFL · Texans ML · 4 min ago | −142 → −156−14¢ in 3 min | FD−140CWithin 2% of fair |
| Patriots vs BillsNFL · Patriots ML · 18 min ago | +250 → +240−10¢ in 3 min | DK+260B+3.4%Stale price |
| Magic vs CavaliersNBA · Cavaliers ML · 22 min ago | −128 → −140−12¢ in 2 min | FollowedNone above fair |
Tickets vs handle: the sharp-side rule
Betting splits show two numbers per side. Tickets is the share of bets; handle is the share of money. When a side’s share of the money runs well ahead of its share of the bets, its average bet is bigger, and big bets are more likely to come from bettors the books respect.
Raiders: 46 − 23 = +23 pts, sharp side. The average Raiders bet is 2.9× the size of the average Chiefs bet.
49ers: 62 − 64 = −2; Broncos: 38 − 36 = +2. Neither reaches 8: the public is on the 49ers, and the money agrees with it.
Read it as a hint, not a verdict. Splits only cover the books that report them, and a big bet is not always a smart one. The rule earns its keep when it agrees with the price: money on a side, and Pinnacle moving toward it.
Reverse line movement
Normally the side taking most of the bets gets more expensive: books shorten its price to slow the flow and balance their risk. Reverse line movement is the opposite: most of the tickets land on one side, and that side’s price gets longer anyway. When the public piles onto a team and the price still drifts against it, someone with more weight than the public is on the other side.
Chiefs vs Raiders, the game in the chart above, is a clean case. 77% of the tickets are on the Chiefs, yet Pinnacle moved the Chiefs from −220 to −192 and the Raiders from +196 to +173. Over the same days the Raiders’ share of the handle grew from 32% on Thursday to 46% today, while their share of tickets stayed between 22% and 24%. Tickets on one side, money and price on the other.
By the time you see it, Pinnacle has already moved, so reverse movement on its own is not a bet. It tells you which game to look at; the edge only exists if a soft book is still dealing the old number. The Game Center puts the 72-hour chart, tickets, handle and every book’s price on one screen.
Locked markets
When news hits, books often suspend a market instead of guessing. The last price can stay visible in their feed, but you cannot bet it, and it no longer means anything: it was set before the news. A frozen quote is the most convincing fake edge there is.
Guru-frat marks a suspended quote is_active: false and keeps it off the board. It cannot be the best price, it does not produce a play or a grade, and it does not count toward the market consensus or the hold. Play-by-Play posts a market-locked event when it happens, and the quote rejoins the board when the book reopens with a new price.
| Side | Frozen at MGM | Fair now | If it counted |
|---|---|---|---|
| Braves ML | +123 | +136 | F−5.6% |
| Dodgers ML | −151 | −136 | F−4.1% |
Neither frozen price would beat fair even if it counted, but the board still drops them: a price you cannot bet is not a price.
Keep going
Then watch it live: steam, line moves and locked markets land in Play-by-Play as they happen, and every game’s 72-hour chart lives in the Game Center. Steam alerts and sharp money flow start at the ALL-PRO league.