Cincinnati Reds vs. Seattle Mariners Prediction July 21

The Cincinnati Reds vs. Seattle Mariners prediction leans heavily toward the over on the first five innings total, with the YES outcome carrying a 74 percent implied probability on Polymarket entering Tuesday night’s contest at T-Mobile Park. The market surged 27.5 percent in the last 24 hours, driven by large whale-sized positions stacking the over-2.5-runs side hard in a brand-new market that opened Monday.

Momentum tells one clear story here: the 1-hour reading is flat, but the 24-hour climb of 27.5 percent combined with a trend score of 32.69 signals a cooling after a sharp early run-up — not a reversal. The Seattle Mariners sit at roughly 26 percent implied probability on the NO side (under 2.5 runs through five innings), while the YES outcome resolves if either club contributes enough offense to push the first-five-innings run total above 2.5. The game tips off July 21, 2026, and the market closes July 29, 2026. Total lifetime volume stands at $300,531.

Where the Big Money Landed

Large traders have committed a combined $109,716 exclusively to the YES side over the last seven days, with zero dollars placed on the NO outcome. Every whale-sized position has landed on the over-2.5-runs outcome, signaling broad conviction among the biggest players that early-innings scoring is likely. Two traders lead the charge, each entering at similar price levels with sizable stakes.

The single largest position belongs to wallet 0xcd30…f316, who committed $58,560 to the YES outcome. A second notable trader, wr0ngw4yb3tt0r, placed $51,156 on YES and currently carries a profit of $15,400 on the position. Both entered the market early, and the price has moved meaningfully in their favor since their entries.

The whale pattern here is straightforward: large capital is not split. When every major position in a market points to one outcome, that concentration tends to reflect informed expectations rather than random noise. The overall market price of 74 percent YES aligns tightly with where the whales are parked, confirming rather than diverging from the crowd signal.

How To Read This Table

• Trader: Wallet name or abbreviated address from the prediction market leaderboard.
• Amount: Total position size in USD committed to this specific market.
• Team Backed: Which team (outcome) the trader bought.
• ROI: The trader’s all-time return on investment across all markets, showing track record reliability.

Game Stats

• Players
• Team

Batters	AVG	HR	RBI	H
S.Stewart 1B	0.253	20	70	95
S.Steer 1B	0.246	16	40	81
E.De La Cruz SS	0.282	16	45	89
M.McLain 2B	0.190	8	25	51
E.Suárez 3B	0.210	12	36	53
J.Bleday LF	0.243	16	43	61
T.Stephenson C	0.247	8	27	58
N.Lowe 1B	0.249	11	30	51
T.Friedl CF	0.175	3	11	34
B.Dunn CF	0.282	2	7	40
N.Marte RF	0.197	6	13	26
K.Hayes 3B	0.138	2	5	18
D.Myers CF	0.260	3	14	32
E.Arroyo 2B	0.236	0	4	25
W.Benson RF	0.188	3	6	18
J.Trevino C	0.268	3	10	19
P.Higgins C	0.231	0	4	6
I.Johnson 2B	0.000	0	0	0

Starting pitcher	W-L	ERA	WHIP	K
C.Burns SP	11-1	2.54	1.11	118

Pitchers	W-L	ERA	WHIP	K
A.Abbott SP	5-5	4.11	1.42	84
C.Burns SP	11-1	2.54	1.11	118
B.Singer SP	4-9	4.56	1.41	82
R.Lowder SP	3-7	5.75	1.64	61
N.Lodolo SP	3-2	4.60	1.47	50
B.Burke RP	3-4	2.89	1.35	40
S.Moll RP	1-6	4.43	1.35	44
T.Santillan RP	1-4	5.23	1.39	28
T.Antone RP	1-0	2.17	0.90	26
P.Johnson RP	2-1	4.08	1.26	26
B.Williamson SP	2-3	6.11	1.64	19
C.Phillips RP	1-0	5.53	1.77	28
G.Ashcraft RP	1-1	3.33	1.22	32
C.Petty SP	1-2	4.38	1.10	11
C.Ferguson RP	1-0	3.20	1.42	19
E.Pagán RP	2-1	6.23	1.44	18
J.Franco SP	0-0	5.40	1.92	13
H.Greene SP	2-1	6.06	1.16	26
J.Garcia RP	0-2	2.77	0.92	13
Z.Maxwell RP	0-1	9.90	2.40	9
L.Mey RP	0-0	7.27	1.96	14
K.Nicolas RP	1-0	8.59	2.86	7
B.Leibrandt SP	0-0	7.50	2.17	3
J.Trevino C	0-0	14.40	3.00	1
Z.McCambley SP	0-0	6.23	2.54	4
L.Richardson RP	0-1	27.00	2.40	3
P.Higgins C	0-0	0.00	0.00	1
Y.Marte RP	0-0	108.00	12.00	1
E.Suárez 3B	0-0	0.00	0.00	0
K.Hayes 3B	0-0	0.00	0.00	0
T.Stephenson C	0-0	0.00	0.00	0
W.Benson RF	0-0	0.00	0.00	0
T.Friedl CF	0-0	0.00	0.00	0
N.Lowe 1B	0-0	0.00	0.00	0
M.McLain 2B	0-0	0.00	0.00	0
N.Marte RF	0-0	0.00	0.00	0
D.Myers CF	0-0	0.00	0.00	0
J.Bleday LF	0-0	0.00	0.00	0
I.Johnson 2B	0-0	0.00	0.00	0
S.Steer 1B	0-0	0.00	0.00	0
E.Arroyo 2B	0-0	0.00	0.00	0
E.De La Cruz SS	0-0	0.00	0.00	0
B.Dunn CF	0-0	0.00	0.00	0
S.Stewart 1B	0-0	0.00	0.00	0

INJURY REPORT

NAME	POS	STATUS	INJURY	NOTES
Ke'Bryan Hayes	POS 3B	STATUS Out	INJURY Back	Notes Hayes is dealing with a lumbar bulging disk and has been placed on the 10-day injured list.
Tony Santillan	POS RP	STATUS Out	INJURY Oblique	Notes Santillan is dealing with an oblique strain and has been placed on the 15-day injured list.
Hunter Greene	POS SP	STATUS Out	INJURY Elbow	Notes Greene is recovering from right elbow surgery and has been placed on the 60-day injured list. He is expected to be out until mid-July.
Dane Myers	POS CF	STATUS Out	INJURY Shoulder	Notes Myers is dealing with a left shoulder contusion and has been placed on the 10-day injured list.
Graham Ashcraft	POS RP	STATUS Out	INJURY Forearm	Notes Ashcraft is dealing with a right forearm UCL sprain and has been placed on the 60-day injured list.
Brandon Williamson	POS SP	STATUS Out	INJURY Shoulder	Notes Williamson is dealing with left shoulder fatigue and has been placed on the 60-day injured list.
Blake Dunn	POS CF	STATUS Out	INJURY Elbow	Notes Dunn is dealing with an injury to his right elbow and has been placed on the 10-day injured list.

full roster and injuries

Batters	AVG	HR	RBI	H
J.Naylor 1B	0.253	8	37	92
C.Young 2B	0.256	13	48	92
J.Rodríguez CF	0.256	14	41	90
R.Arozarena LF	0.281	11	45	94
J.Crawford SS	0.215	10	28	63
C.Raleigh C	0.163	9	29	41
L.Raley RF	0.230	15	37	56
D.Canzone DH	0.261	15	40	61
C.Emerson SS	0.195	7	20	30
M.Garver C	0.184	4	14	21
R.Refsnyder DH	0.133	3	9	14
V.Robles RF	0.210	0	5	21
L.Rivas 3B	0.131	0	7	13
B.Donovan 3B	0.274	3	8	23
J.Pereda C	0.270	2	4	17
W.Wilson 3B	0.220	2	7	13
P.Wisdom 3B	0.122	1	4	5
C.Joe RF	0.179	1	3	7
M.Mastrobuoni 3B	0.192	0	1	5
B.Kennedy 1B	0.071	0	0	1
R.Bliss 2B	0.125	0	1	1
W.Wilson 3B	0.200	1	2	1

Starting pitcher	W-L	ERA	WHIP	K
L.Castillo SP	3-8	4.93	1.37	81

Pitchers	W-L	ERA	WHIP	K
L.Gilbert SP	8-6	3.38	0.98	129
B.Woo SP	7-6	4.16	1.09	109
G.Kirby SP	7-8	3.76	1.32	98
E.Hancock SP	6-4	3.17	1.01	94
L.Castillo SP	3-8	4.93	1.37	81
B.Miller SP	4-4	2.27	0.88	71
E.Bazardo RP	3-2	2.29	1.22	44
J.Ferrer RP	3-1	2.85	1.37	35
A.Muñoz RP	3-4	3.96	1.21	55
C.Criswell RP	2-1	3.52	1.17	23
G.Speier RP	1-2	2.05	1.14	21
A.Hoppe RP	0-1	6.38	1.46	26
N.Davila RP	0-0	3.54	1.18	9
C.Wilcox RP	0-0	4.00	1.72	18
M.Brash RP	3-0	0.54	0.84	15
M.Rucker RP	0-2	5.27	1.46	14
D.Gonzalez RP	0-0	4.70	1.83	5
J.Simpson RP	0-0	9.00	2.00	3
W.Wilson 3B	0-0	15.43	2.57	0
B.Kennedy 1B	0-0	36.00	6.00	0
M.Garver C	0-0	0.00	0.00	0
R.Refsnyder DH	0-0	0.00	0.00	0
J.Crawford SS	0-0	0.00	0.00	0
C.Joe RF	0-0	0.00	0.00	0
J.Naylor 1B	0-0	0.00	0.00	0
V.Robles RF	0-0	0.00	0.00	0
P.Wisdom 3B	0-0	0.00	0.00	0
R.Arozarena LF	0-0	0.00	0.00	0
J.Rodríguez CF	0-0	0.00	0.00	0
L.Rivas 3B	0-0	0.00	0.00	0
L.Raley RF	0-0	0.00	0.00	0
J.Pereda C	0-0	0.00	0.00	0
C.Raleigh C	0-0	0.00	0.00	0
M.Mastrobuoni 3B	0-0	0.00	0.00	0
B.Donovan 3B	0-0	0.00	0.00	0
W.Wilson 3B	0-0	0.00	0.00	0
R.Bliss 2B	0-0	0.00	0.00	0
D.Canzone DH	0-0	0.00	0.00	0
C.Young 2B	0-0	0.00	0.00	0
C.Emerson SS	0-0	0.00	0.00	0

INJURY REPORT

NAME	POS	STATUS	INJURY	NOTES
Rob Refsnyder	POS DH	STATUS Out	INJURY Knee	Notes Refsnyder is dealing with injuries to both knees and has been placed on the 10-day injured list.
Luke Raley	POS RF	STATUS Questionable	INJURY Forearm	Notes Raley is dealing with a forearm injury and is uncertain to take the field for the Mariners.
Brendan Donovan	POS 3B	STATUS Out	INJURY Groin	Notes Donovan is dealing with a left groin muscle strain and has been placed on the 10-day injured list.
Matt Brash	POS RP	STATUS Out	INJURY Lat	Notes Brash is dealing with a right lat strain and has been placed on the 15-day injured list. He is expected to return in mid-August.
Will Wilson	POS 3B	STATUS Out	INJURY Thumb	Notes Wilson is dealing with a left thumb fracture and has been placed on the 60-day injured list.
Cooper Criswell	POS RP	STATUS Out	INJURY Shoulder	Notes Criswell is dealing with a right shoulder strain and has been placed on the 15-day injured list. He is expected to return in mid-August.

full roster and injuries

CIN

SEA

33.51

At Bats

33.00

4.18

Runs

4.06

764

Hits

765

3.64

Walks

3.34

9.37

Strikeouts

8.58

0.309

On Base Percentage

0.310

0.399

Slugging Percentage

0.378

4.61

Earned Run Average

3.57

4.56

Earned Runs

3.51

1.35

Home Runs

0.94

4.34

Walks

2.49

800

Strikeouts

871

0.08

Strikeouts Per 9 Innings

0.09

1.44

Walks Plus Hits Per Inning Pitched

1.17

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How the Cincinnati Reds vs. Seattle Mariners First-Five-Innings Market Resolves

The YES outcome resolves if the combined run total through the first five innings of Tuesday’s game exceeds 2.5 — meaning three or more runs scored between the Cincinnati Reds and the Seattle Mariners in the opening half of the game. The NO outcome resolves if the two teams combine for two or fewer runs through five innings. There is no draw scenario; the market settles binary.

• Cincinnati Reds (YES — Over 2.5 Runs in First Five Innings): 74%
• Seattle Mariners (NO — Under 2.5 Runs in First Five Innings): 26%

The Cincinnati Reds arrive in Seattle riding some positive momentum after outfielder Eugenio Suárez hit a solo home run against the Colorado Rockies on July 17 — a sign that the Cincinnati lineup carries real pop right now. The Seattle Mariners carry a 50-50 record through 100 games, a team that has battled to stay competitive but has not dominated on either side of the ball consistently. A 50-50 Seattle club at home facing a Reds team showing offense is exactly the kind of setup that produces early scoring.

Market Signals and Form

The momentum composite across 1-hour and 24-hour windows, alongside the trend score of 32.69, reads as a market that sprinted hard on Monday and is now digesting those gains without giving them back. The 24-hour gain of 27.5 percent was the catalyst, likely tied to starting pitcher news or lineup confirmations that surfaced Monday. The trend score in the low-30s confirms that the move is real but the pace has slowed.

Total volume hit $300,531 with $300,103 of that arriving in the last 24 hours alone, meaning this market essentially opened and immediately drew serious liquidity. Available liquidity sits at $726,284, which is nearly 2.5 times total committed volume — a sign the market can absorb large new positions without meaningful price slippage.

The game-level spread sits at -1.5 with a full-game over/under of 7.5. Same-sport correlation data does not yield a qualifying same-event or same-league market this cycle, so no cross-market signal is applicable here.

• 24-hour volume: $300,103 — nearly the entire market volume arrived Monday, reflecting a rapid-entry market
• Liquidity: $726,284 — deep enough to support large new positions without moving the price sharply
• Momentum composite: 24-hour surge of 27.5 percent now cooling; trend score of 32.69 signals stabilization, not reversal
• Whale concentration: 100 percent of large-trade capital on YES, zero on NO — no divergence from market price
• Reds offense: Eugenio Suárez connected for a home run on July 17, and Chase Burns is locked into Cincinnati through 2034 on a seven-year extension — a stable, invested rotation anchor

Lines Analysis: Cincinnati Reds First-Five-Innings Total

The 74 percent YES probability reflects a market that sees three or more early-innings runs as the base case. The Cincinnati Reds bring a lineup with proven power — Suárez’s recent home run is a data point — and the Seattle Mariners, sitting at exactly .500, have not demonstrated the lockdown pitching needed to suppress a motivated visiting offense through five innings consistently.

The NO outcome at 26 percent is not impossible. Seattle pitching has shown capable stretches, and T-Mobile Park can suppress run totals on cold Pacific Northwest nights. If Seattle’s starter is sharp from the first pitch and the Reds’ lineup goes cold early, a sub-three-run five innings is achievable. But the market prices that outcome as clearly secondary.

• Watch starting pitcher status: Any confirmed scratches or late lineup changes before first pitch at 9:40 PM ET could shift the market quickly
• Cincinnati lineup construction: Power hitters near the top of the order increase the probability of early contact and runs
• Seattle starter effectiveness: If the Mariners’ arm struggles in the first two innings, the market price will hold or extend
• Weather and park factors: T-Mobile Park plays as a pitcher’s park in some conditions; a cool night marginally supports the NO side
• Volume stability: With $726,284 in available liquidity, any late-breaking news will price in fast — monitor for pre-game activity

With $300,531 in total volume — nearly all of it placed in a 24-hour window — this market reflects a well-informed, concentrated consensus. When whale capital, overall price, and 24-hour momentum all point the same direction, the signal is rarely ambiguous.

LINES VERDICT

CINCINNATI REDS (YES — Over First Five Innings)

The Cincinnati Reds offense shows genuine run-scoring form entering Tuesday, whale capital is entirely committed to the YES side, and the market has absorbed a massive 24-hour surge without giving ground — making the over outcome the clear market-backed call.