Cardinals vs Pirates Prediction Market Odds, September 23, 2026
| Spread | Total | ML | Best ML | |
|---|---|---|---|---|
â–¶Cardinals | +1.5 63%63% | O 7.5 47%48% | 44%44% | 44% Kalshi |
â–¶Pirates | -1.5 37%37% | U 7.5 53%52% | 57%56% | 57% Kalshi |
| Spread | Total | Moneyline | Best ML | |
|---|---|---|---|---|
â–¶St. Louis Cardinals | +1.5 | O 7.5 | 44% Kalshi | |
â–¶Pittsburgh Pirates | -1.5 | U 7.5 | 57% Kalshi |
Pittsburgh (80-77) is the 53% favorite on both Kalshi and Polymarket for the middle game of this three-game set at PNC Park, after shutting out St. Louis 2-0 in Tuesday's opener. The Cardinals (76-81) sit at 48% on Kalshi and 47% on Polymarket, having climbed roughly three points overnight. Both teams are eliminated from postseason contention, leaving the Pirates' push for a winning season as the live stake. About $47K of volume spans 316 lines; the live board above carries current prices.
Pittsburgh opened the final home series of its season by shutting out St. Louis 2-0 on Tuesday, and the market has responded by shaving the Pirates down rather than pushing them up. Pittsburgh (80-77) is the 53% favorite on both Kalshi and Polymarket for the middle game, with St. Louis (76-81) at 48% on Kalshi and 47% on Polymarket. Both clubs were eliminated from postseason contention before this series began, so the stakes here are record-shaped: the Pirates need two wins in their last five games to finish above .500, and the Cardinals, at five games under with five to play, cannot.
Cardinals vs Pirates Market Context
The home side has the better team profile on both sides of the ball. Pittsburgh ranks 4th in the majors in team batting average (.254) and 5th in runs scored (750), against a 4.16 staff ERA that sits 17th. St. Louis is 20th in average (.241), 13th in runs (704), and 21st in ERA (4.28). Brandon Lowe leads the Pirates with 33 home runs and 93 RBI, and Nick Gonzales is hitting .302. Alec Burleson carries the Cardinals at .280 with 111 RBI, with Jordan Walker at 28 home runs.
Venue splits reinforce the price. Pittsburgh is 43-36 at PNC Park and 37-41 away from it, while St. Louis is an even 38-38 on the road against a 38-43 mark at home. A 53% home favorite is close to the least a market will pay for home field with a run-scoring edge attached, which tells you the board is discounting the pitching matchup rather than the rosters.
As of Wednesday morning, Matthew Liberatore (5-14, 5.36 ERA) is listed as the St. Louis probable and Lake Bachar (1-4, 3.56 ERA) as the Pittsburgh probable. Bachar is a relief arm by position, which points at a bullpen game or a short outing behind an opener, and that is the single most likely reason the Pirates are priced this thin at home after winning the opener.
What the Cardinals vs Pirates Run Line and Total Imply
The run line is symmetric and unusually so. Pittsburgh at -1.5 prices at 35% and St. Louis at -1.5 prices at 35%, which is the market saying the identity of the winner is nearly a coin flip and a multi-run margin is roughly a one-in-three outcome either way. The -2.5 rungs sit at 25% for Pittsburgh and 26% for St. Louis, so the board sees no asymmetry in blowout risk at all.
The total is where the real move happened. Over 7.5 runs traded near 53% on Polymarket and 53% on Kalshi in the Tuesday evening captures and is down to 47% on Kalshi and 46% on Polymarket by Wednesday morning, a six-point slide against a backdrop of a 2-0 shutout the night before. The adjacent rungs are consistent with that repricing: Over 6.5 sits at 59.5%, Over 8.5 at 39.5%. A run in the first inning prices at 45.5%.
The moneyline moved the same direction over the same window. Pittsburgh was 55% on both venues in the earliest captures and is 53% on Kalshi and 52% on Polymarket now, with St. Louis climbing from 45% on Kalshi to 48%. Those captures reach back to roughly 8:00 PM ET Tuesday, so this is an overnight drift toward the visitor and the under, not a full open-to-now picture.
Cross-platform, there is almost nothing to arbitrage. The moneyline spread is one point on the St. Louis side and zero on the Pittsburgh side, and the total is within one point. Kalshi is the marginally better venue for a St. Louis buyer at 48% versus 47%, and Polymarket the better one for selling Pittsburgh. That is a tight, well-arbitraged board rather than a value spot.
When the Cardinals vs Pirates Market Resolves
The moneyline resolves to the team that wins the game at PNC Park on September 23, 2026, first pitch 6:40 PM ET, with the broadcast on MLB.TV and Cardinals.TV. Run line and total contracts settle on the official final score, including extra innings. First-five-inning markets settle on the score after five completed innings. Contracts pay $1 per share on the winning side and $0 otherwise. A postponement moves settlement to the completed makeup game or voids per each platform's rules, and a rain-shortened game settles on the official score once the game is called.
Key Cardinals vs Pirates Catalysts
Pitching shape: Lake Bachar is a reliever by position with a 3.56 ERA over a 1-4 record, so how deep Pittsburgh gets before going to the pen is the game's swing variable.
The Liberatore problem: the listed St. Louis starter carries a 5.36 ERA and a 5-14 record, which is why a 76-81 road team is still priced at 47.5% against a winning club.
Overnight total move: Over 7.5 fell from about 53% to 46.5% across the captured window, so the market is pricing a second straight low-scoring game after Tuesday's 2-0 final.
Home split: Pittsburgh is 43-36 at PNC Park and this is the closing home stand of its season, with a winning record two victories away.
Symmetric run line: both -1.5 sides price at 35%, so any read that one team is materially more likely to win by multiple runs is a disagreement with the board, not an echo of it.
Related Cardinals vs Pirates Markets
The season-long context trades separately: the Pirates season win total is the direct expression of whether Pittsburgh finishes above .500, and the Cardinals season win total has already settled its ceiling at 81. Team-level pricing and the rest of the schedule live on the Pittsburgh Pirates hub and the St. Louis Cardinals hub. For the rest of Wednesday's slate, including games with live postseason seeding at stake, see the MLB league hub and the Rays at Yankees board.
Resolution Criteria
The moneyline resolves to the team that wins the game at PNC Park on September 23, 2026, scheduled for 6:40 PM ET. Run line and total-runs contracts settle on the official final score including extra innings, and first-five-inning markets settle on the score after five completed innings. Each winning contract pays $1 per share and every other contract resolves to $0. If the game is postponed, settlement moves to the completed makeup game or the contract voids according to each platform's rules, and a game called early settles on the official score once it becomes an official game.
Key Factors
- Lake Bachar (1-4, 3.56 ERA) is the listed Pittsburgh probable as of Wednesday morning and is a reliever by position, so bullpen depth is the swing variable
- Matthew Liberatore (5-14, 5.36 ERA) is the listed St. Louis probable, the main reason a 76-81 road team prices at 47.5%
- Over 7.5 runs slid from about 53% to 46.5% across the captured overnight window, following Tuesday's 2-0 final
- Pittsburgh is 43-36 at PNC Park and needs two wins in its last five games to finish above .500
- Both run lines at -1.5 price at 35%, so the board sees no asymmetry in blowout risk
- Cross-platform spread is one point or less on every primary line, leaving no meaningful venue arbitrage
What are the Cardinals vs Pirates odds for September 23, 2026?
As of the morning of September 23, 2026, Pittsburgh is the favorite at 53% on both Kalshi and Polymarket. St. Louis trades at 48% on Kalshi and 47% on Polymarket, for a 47.5% cross-platform average.
Where can I trade the Cardinals vs Pirates game?
The game trades on both Kalshi and Polymarket. Prediction Genius shows both venues side by side across the moneyline, the run line, total runs, first-five-inning markets, and player props, 316 lines in all.
Who is favored in Cardinals vs Pirates and by how much?
Pittsburgh is favored with a 53% implied probability, a narrow edge worth roughly six points over St. Louis at 47.5%. The Pirates are 43-36 at home and won the series opener 2-0.
What is the run line and total for Cardinals vs Pirates?
Both run lines are symmetric: Pittsburgh -1.5 and St. Louis -1.5 each price at 35%. Over 7.5 total runs sits at 46.5%, down from about 53% overnight, with Over 6.5 at 59.5% and Over 8.5 at 39.5%.
When does the Cardinals vs Pirates market resolve?
First pitch is 6:40 PM ET on September 23, 2026 at PNC Park, on MLB.TV and Cardinals.TV. Contracts settle on both platforms once the game goes final, usually within a few hours of the last out.