Celta and Betis should trade possession spells, but their recent entries have not turned into the same quality of first shot. In Rotterdam, Ajax can press high while Sparta look for direct passes and second balls. Both games are likely to hinge on what happens after the first clearance. Wide players and restarts give each side an early way to change the rhythm.
Celta's Álvarez and Rodríguez have combined well on wide runs and dead balls, while Antony and Abde can release Parrott through the spaces behind Celta's wingbacks. Borja Iglesias and Starfelt are missing from Celta's match squad and both missed Celtic; Betis are also without Cucho Hernández and Firpo, but Parrott, Roca, Antony, Abde and both central defenders played against Feyenoord. Celta's recent wins relied on sharp finishes from limited clean chances, whereas Betis have kept their creative chain intact. I expect Betis to produce the better central finish, so I'm siding with Betis.
Ajax's press can trouble Sparta's first pass, but Sparta's long outlet to Zonneveld and Toornstra's second-ball service have created box chances with little possession. Mito is out and missed Willem II, yet Babadi, Toornstra, Martes, Kuipers and Zonneveld made that replacement attack work. Ajax's missing attackers also missed Atalanta, where plenty of shots brought a late breakthrough rather than repeated clean finishes. Sparta have an active reply to Ajax territory, so I'm siding with Sparta to keep this contest close.