Jackson Chourio Under 1.5 Total Bases: MLB AI Pick for September 18, 2026
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Win probability is the models' chance the side hits. Edge is the gap between that win chance and the price the book is offering. Recommended props get a green star in-app so the full slate stays visible, including cautioned spots with a plain-language reason.
For September 18, 2026, the models are on Jackson Chourio Under 1.5 Total Bases (-126) when the Brewers visit the Orioles. First pitch is listed around 6:05 PM on the live card. The prop models project about 1.2 total bases, with a 58.7% win chance and +6.7% Edge on the app card. The spot carries Elite Edge and a recommended green star, which is how Rithmm marks stronger model-to-market gaps on the slate.
Chourio's own total-bases Unders sit at 13-9 in the tracked sample, about a 59% hit rate with positive ROI, and the recent half of that bucket is closer to 9-5. That is a named-player lane, not a random left fielder label, and it lines up with the same Under the models are posting tonight in Baltimore.
The broader Elite Edge total-bases Under read backs the direction. When batter total-bases Unders land with Elite Edge, the larger sample runs about 114-69, roughly a 62% hit rate and strong ROI. Tightening that lane to the EV band that matches this price has gone about 94-56 with a similar mid-60s win rate. September total-bases Unders as a month bucket sit near 108-72. Those are supporting lanes, not separate picks. The featured bet is still one prop: Chourio Under 1.5.
The projection gap is modest in raw bases and clearer once you price the juice. At a 1.5 line, 1.2 projected total bases keeps the Under on the right side of multi-hit and extra-base nights without needing a zero. The bar on the card shows the Under side near 59% with the Over near 41%, which is the same story as the win chance and Edge pair. Shop the number before you lock it. A few cents of juice change how much of that +6.7% Edge you keep after the hold.
Use the Bet Info tab for the live projection, win chance, and Edge, then check line shopping so you are not stuck on the worst book. Trends and recent form across the last 5, 10, and 20 games sit next to the number if you want a quick form check without leaving the prop. Injuries feed the models continuously, so you are not hand-editing a spreadsheet after every lineup tweet.
If you want the plain-English read on why Chourio is under this line against Baltimore, open Scout on Pro or Premium and ask what the models like about the Under, where the Edge is coming from, and how the price compares after you shop. Scout will not promise a lock. It will walk the projection, the market, and the why in normal language so you can decide with a clearer board.
This is a single AI sports picks feature for the night, not a parlay sheet. Build around it only if your bankroll rules allow correlated or same-game structure, and size it for a juiced favorite Under. For more AI MLB picks and the rest of today's board, open Rithmm, filter MLB props, and read Chourio next to the full slate before first pitch.
Plans start on Core, with Pro and Premium unlocking Scout if you want the analyst layer on top of the models. Pricing and tier detail live on the Rithmm pricing page. Pull the live card in-app before you bet. Lines move, and the app card is the source of truth for Edge, win chance, and game time on game day.
