Reds vs Diamondbacks Prediction Market Odds, August 22, 2026
| Spread | Total | ML | Best ML | |
|---|---|---|---|---|
Reds | +1.5 — | O 1 — | 100%100% | 100% Kalshi |
Diamondbacks | -1.5 — | U 1 — | 0%0% | — |
| Spread | Total | Moneyline | Best ML | |
|---|---|---|---|---|
Cincinnati Reds | +1.5 — | O 1 — | 100%100% | 100% Kalshi |
Arizona Diamondbacks | -1.5 — | U 1 — | 0%0% | — |
Arizona is the 62c favorite over Cincinnati at Chase Field, and Kalshi and Polymarket quote the identical number, leaving no cross-platform gap on the moneyline. The Diamondbacks (68-61) send Michael Soroka (8-3, 2.93 ERA) against Rhett Lowder (4-8, 5.17 ERA) for the Reds (61-68), the widest starter ERA split on the slate, one night after Arizona won the opener 9-0. First pitch is 8:10 PM ET.
Arizona is the 62c favorite at home against Cincinnati on Saturday evening at Chase Field, and Kalshi and Polymarket have landed on the exact same number. The Diamondbacks (68-61, 37-27 at home, third in the NL West) opened this series by shutting out the Reds 9-0 on August 21, and the board has drifted their way since. Cincinnati (61-68, 29-32 on the road, fifth in the NL Central) sits at 39c and sends Rhett Lowder (4-8, 5.17 ERA) against Michael Soroka (8-3, 2.93 ERA), the widest starting-pitcher ERA gap on the slate. First pitch is 8:10 PM ET (5:10 PM local in Phoenix), a time confirmed by both the Kalshi game ticker and the ESPN scoreboard entry.
Reds vs Diamondbacks Odds Across Kalshi and Polymarket
| Market | Line | Kalshi | Polymarket | Consensus |
| Moneyline | Arizona Diamondbacks | 62c | 62c | 62c |
| Moneyline | Cincinnati Reds | 39c | 39c | 39c |
| Run line | Arizona Diamondbacks -1.5 | 43c | 43c | 43c |
| Run line | Cincinnati Reds -1.5 | 28c | 28c | 28c |
| Total | Over 7.5 runs | 54c | 54c | 54c |
| Total | Over 8.5 runs | 45c | 45c | 45c |
| First inning | Run scored in the 1st | 50c | 49c | 49.5c |
Prices as of August 22, 2026. The live board above this article carries the current numbers.
The 62c/39c pair sums to 101c, which is about as tight a two-sided book as a mid-August National League game produces. Devigged, Arizona is a 61% side. What is notable is the absence of a cross-platform gap: on the moneyline, the run line at -1.5, and the 7.5-run total, Kalshi and Polymarket quote identical cents. The only daylight anywhere on the board is a single cent on the first-inning run market (50c Kalshi, 49c Polymarket) and on the 9.5-run total (35c Kalshi, 36c Polymarket), which is inside the tick size and not a pricing disagreement worth acting on. Traders looking for a cross-platform edge on this game will not find one; the value question here is whether 62c is the right number at all, not which venue has the better version of it.
The board has traded roughly $47.5K in lifetime volume across both platforms, with the Kalshi Arizona-wins contract ($17.0K), the first-inning run market ($12.8K), and the Arizona -3.5 spread ($11.4K) carrying most of it. That is a thin-to-average regular-season game book, so single orders move these lines more than they would on a division leader's game.
The Soroka vs Lowder Pitching Matchup Drives the Reds vs Diamondbacks Price
Soroka's 2.93 ERA is the single biggest input into Arizona's 62c. He is 8-3 on the season, and the strikeout ladder prices him as a volume arm: 4-plus strikeouts sits at 86c, 5-plus at 74c, and 6-plus at 58c, which puts his implied median right around five and a half. Lowder's ladder is a full tier lower, with 3-plus strikeouts at 72c and 4-plus at 50c, an exact coinflip.
Lowder's 5.17 ERA is why Cincinnati is a 39c dog despite a record just seven games worse than Arizona's. The run line reflects that: Arizona -1.5 is 43c, meaning the market gives the Diamondbacks a 43% chance of winning by two or more, versus 28c for Cincinnati to do the same. That 15c gap is the cleanest statement of how the two starters are being valued.
Both offenses are priced for a normal night rather than a blowout. Arizona's team total sits at 76c to clear 2.5 runs and 46c to clear 4.5; Cincinnati's is 63c to clear 2.5 and 46c to clear 3.5. Corbin Carroll is 69c to record a hit and 16c to go deep; Elly De La Cruz is 68c and 14c on the same two props. Neither star is priced as the deciding variable, which is consistent with a board that is pricing the starters, not the lineups.
Where the Reds vs Diamondbacks Line Has Moved
The board carries 27 snapshot captures on the moneyline stretching back to roughly 8:40 PM ET on August 21, immediately after Arizona's 9-0 shutout. Arizona opened that window at 60c and has ticked up to 62c, with Cincinnati sliding 41c to 39c. It is a two-cent drift, not a repricing, and it moved in the direction the series result would suggest.
The total has moved slightly more in percentage terms. Over 7.5 runs opened the window at 51c and now trades at 54c, having touched 55c, so the market has added about three cents of run expectation since the shutout. The Arizona -3.5 spread has gone the other way, 25c to 24c, meaning the money is buying runs in the aggregate without buying an Arizona blowout specifically. Recent form supports a modest read on both clubs: Arizona is 5-5 in its last ten and Cincinnati is 4-6, and Cincinnati has scored two runs or fewer in five of those ten games.
When the Reds vs Diamondbacks Market Resolves
Every contract on this board settles on the final score of the Reds at Diamondbacks game at Chase Field on August 22, 2026. The moneyline pays out to the winning team, the run line settles on the margin, and the totals settle on combined runs scored, all after the game is official. First-five-inning markets settle on the score after five complete innings regardless of the final result. Both Kalshi and Polymarket typically finalize within a few hours of the last out.
Key Reds vs Diamondbacks Catalysts
Soroka's strikeout volume: 6-plus strikeouts at 58c is the market's read on whether Arizona's starter controls the game outright.
Lowder's command: a 5.17 ERA is the reason Cincinnati is 39c, and an early crooked number turns the 54c over into the live side.
The first-inning run market at 49.5c: the most-traded prop on the board after the moneyline, and a direct proxy for which starter settles in first.
Cincinnati's road scoring: 29-32 away from Great American Ball Park, with two runs or fewer in five of the last ten games overall.
No cross-platform spread: Kalshi and Polymarket quote identical moneyline, run-line, and total prices, so venue selection is not a source of edge on this game.
Series momentum after the 9-0 opener: Arizona has moved 60c to 62c since the shutout, a real but small drift.
Related Reds vs Diamondbacks Markets
Arizona's season-long picture trades on the 2026 NL West market, where the Diamondbacks sit third at 68-61, while Cincinnati's is priced on the 2026 NL Central market. Both clubs also appear on the 2026 World Series board and the 2026 NL pennant board. For every open contract on either club, see the Arizona Diamondbacks hub and the Cincinnati Reds hub, or browse the full MLB prediction market slate.
Resolution Criteria
All contracts settle on the outcome of the Cincinnati Reds at Arizona Diamondbacks game at Chase Field in Phoenix on August 22, 2026, with a scheduled first pitch of 8:10 PM ET. The moneyline resolves to the team that wins the game, paying $1 per share on the winner and $0 on the loser. Run-line contracts settle on the final margin of victory, and total contracts settle on combined runs scored by both teams. First-five-inning markets settle on the score after five complete innings, independent of the final result. If the game is postponed, suspended, or shortened, Kalshi and Polymarket apply their own official-game and postponement rules, which generally void or roll contracts rather than settling them on a partial score.
Key Factors
- Michael Soroka (8-3, 2.93 ERA) start quality, with 6-plus strikeouts priced at 58c
- Rhett Lowder (4-8, 5.17 ERA) command, the reason Cincinnati is a 39c underdog
- First-inning run market at 49.5c, the second-most-traded contract on the board
- Cincinnati road offense (29-32 away, two runs or fewer in five of the last ten games)
- Zero cross-platform spread on the moneyline, run line, and 7.5-run total
- Arizona drift from 60c to 62c since the 9-0 series opener on August 21
What are the current Reds vs Diamondbacks odds?
As of August 22, 2026, Arizona is the 62c favorite and Cincinnati is 39c, with Kalshi and Polymarket quoting identical prices on both sides. That implies about a 61% win probability for the Diamondbacks after removing the vig.
Who is favored in Reds vs Diamondbacks?
Arizona is favored at 62c, driven mainly by the pitching matchup: Michael Soroka carries a 2.93 ERA against Rhett Lowder at 5.17. Arizona is also 37-27 at Chase Field this season.
Where can I trade the Reds vs Diamondbacks market?
Both Kalshi and Polymarket list this game, and the board has traded roughly $47.5K in lifetime volume across the two platforms. The Kalshi Arizona-wins contract alone accounts for about $17.0K of that.
What is the Reds vs Diamondbacks run line and total?
Arizona -1.5 trades at 43c and Cincinnati -1.5 at 28c. The total is priced at 54c for over 7.5 runs and 45c for over 8.5 runs, both identical across Kalshi and Polymarket.
When does the Reds vs Diamondbacks market resolve?
It resolves on the final score of the August 22, 2026 game at Chase Field, first pitch 8:10 PM ET. Both platforms typically settle within a few hours of the last out.
What should I watch before first pitch?
Watch Soroka strikeout pricing, currently 86c for 4-plus and 58c for 6-plus, and the first-inning run market at 49.5c. A late lineup change for either club would move the run line faster than the moneyline.