Cardiff's home press can make the first pass awkward and create an immediate route into the box. West Ham can still progress directly and keep their own wide service going. Slavia Prague should attack Arsenal with wingback runs, restarts and second balls. Arsenal's midfield and set pieces give them a separate response after the first attack.
Cardiff's Moylan and Tanner can turn a regain into service for Salech, while West Ham's recent defensive sequences have left second balls available. Chambers and Lawlor were already absent when Cardiff held Birmingham; Ng played the last match and was described as likely fit, while Bielik may return. West Ham have Bowen and fresh forward options, but Cardiff have an observed answer when pressure comes back at them. That's why I'm siding with Cardiff to stay in the contest.
Slavia's current Ayaosi, Suleiman and Nowak routes produced close finishes and a late response without a full role for Provod or Chorý. Those two missed the Jablonec game, and the coach has limited Provod's expected part here; Arsenal's Saka missed Liverpool, though Rice and Ødegaard still give the visitors several ways to score. Slavia can continue supplying after Arsenal's first goal through crosses and recovered balls. That's why I'm siding with Slavia Prague to keep the match close.