Goals from Craig Dawson, Issa Diop and Jarrod Bowen saw West Ham United record a comfortable 3-0 win over Belgian side KRC Genk at London Stadium.
The result saw manager David Moyes' Irons become the first West Ham side to win their first three games, and keep three consecutive clean sheets, at the start of a European season proper.
As a result of their victory, West Ham move onto nine points - six clear of their three opposing sides in Group H, and just three away from securing a place in the next stage of the competition at the first time of asking.