Will Arsenal FC win on 2026-09-09?
Crossbook compares what two exchanges, Polymarket and Kalshi, charge for the same event, and publishes a permanent scored record of its own forecasts under published rules.
Tracked on one venue, with Crossbook's own call on the record.
Crossbook forecast
- 41.0%against a market price of 54.5% at the timeOpen
Logged 7 Sept 2026, 01:33 UTC
- Reference class: elite-visitor away matches in Europe; three-way outcomes cap most teams' away-win probability in the low-to-mid 30s, and the draw (~25%) is always live [no specific fact; general reasoning]
- Signal: Arsenal's form is genuinely elite — three straight PL wins (7-2 aggregate) in 2026-27 and 8/8 wins in last season's UCL league phase — pushing them well above the generic away base rate (f3, f4, f10)
- Signal: Napoli are weakened — McTominay out after a heart procedure, plus Mazzocchi, Marianucci and Buongiorno injured, and they enter off back-to-back defeats including a home loss to Como (f5, f6, f7)
- Counter-signal: Arsenal travel without Saliba, Timber and Mosquera — their core defensive depth — which meaningfully raises Napoli's scoring chances away in a hostile venue (f8)
- Signal (modest): Historical H2H favors Arsenal (3 wins in 4 European meetings, including a 3-0 aggregate in 2019), though aged squad data makes this weak evidence (f9)
- Narrative discount: the away fixture at the Maradona and short rest after an emotionally intense comeback vs Chelsea argue against over-weighting Arsenal's league form (f1, f2, f3)
What would change it: Confirmation that Arsenal's missing defenders (Saliba, Timber) have been replaced by further injuries to Odegaard/Havertz-level attackers, or that Napoli's lineup is near full strength, would push my estimate below 30%. has_independent_basis: true
Context
Polymarket prices this at 56%. No verified equivalent is currently listed on the other venue, so there is no cross venue comparison on this page.
Volume over the last 24 hours is active, at about $70,033 on the busier venue. It closes in 1 day. Prices this close to resolution move on news rather than on reassessment.
Related markets
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