Sebastien Haller became the first player to score five goals in his first two Champions League appearances as Ajax beat Besiktas 2-0.
The former West Ham striker followed his four-goal salvo against Sporting by netting the second goal on Tuesday night.
The previous best of four goals had been achieved by Marco van Basten, Diego Simeone, Didier Drogba and Erling Haaland.
Ajax have a full haul of six points from their two games in the group following an opening day 5-1 win at Portuguese side Sporting, while struggling Besiktas have lost both their games.