Victor Osimhen scored two penalties as Ajax crumbled in the second half to record their fourth straight Champions League defeat at home to Galatasaray.

The sense of crisis in the Amsterdam Arena deepened as Ajax became only the third Dutch club to lose their opening four matches in the competition, leaving them bottom of the table with 14 goals conceded.

Under-fire coach John Heitinga was forced to bring in Belgian teenager Jordy Mokio as cover for Kenneth Taylor after the midfielder’s red card against Chelsea, as well as Anton Gaaei at right-back after Lucas Rosa was ruled unfit to play.

Heitinga also picked Josip Sutalo and Youri Baas in a rejigged central defence and recalled the experienced Davy Klaassen in a four-man midfield. Youri Regeer was selected on the right-hand side while Oskar Gloukh moved to a withdrawn role behind Wout Weghorst and Mika Godts.

Ajax at least made it to half-time without conceding a goal, but their shortcomings were evident as Gaaei gave away possession and Weghorst was isolated up front.

Osimhen, bought from Napoli in the summer for €75m, broke the deadlock just before the hour mark when he nodded past Remko Pasveer after Leroy Sané had escaped the attentions of Sutalo.

The second goal followed six minutes later when Baas was penalised for handball on a video review, sparking angry gestures from Klaassen, and the Nigerian striker beat Pasveer from the spot.

With 12 minutes to go substitute Gerard Alders handled in the penalty area and once again Osimhen made no mistake.

Ajax’s next match is at home to Benfica on November 25. The Portuguese club are are the only club yet to win a point after going down 1-0 at home to Leverkusen on Wednesday.