Striker Eduardo Da Silva scored his first goal for Arsenal in a 2-1 win over Lazio in the opening game of the Amsterdam tournament on Thursday.
The Brazilian-born Croatia international, granted a work permit on Wednesday, netted with a fine header from a corner 10 minutes into the second half.
Danish midfielder Nicklas Bendtner had fired the London side ahead but Goran Pandev levelled five minutes before halftime.
In other action, 10-man Ajax Amsterdam struck twice in the second half to beat Atletico Madrid 2-0.
Spaniard Gabri headed home the opening goal early in the second half but was sent off in the final minute after elbowing an opponent.
Wesley Sneijder sealed the home side's victory on the hour with a superb long-distance volley.
Arsenal and Ajax are both in the lead with five points, three for the win and one for each goal scored, and will meet on Saturday.
