Willian provided two assists on his Arsenal debut as the Gunners eased past Fulham 3-0 at Craven Cottage.
Fulham gave Arsenal an early scare when Aboubakar Kamara drew a smart save from Bernd Leno.
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However, Alexandre Lacazette opened the scoring on the eighth minute.
He tapped in after Marek Rodak had pushed Willian’s shot to him.
In so doing, the forward became the first player to score the first goal of a Premier League season more than once.
Three minutes after the break, Willian, who also struck a post with a free-kick, sent over a corner that was headed in by another debutant, Gabriel.
Pierre-Emerick Aubameyang collected Willian’s long pass to curl in Arsenal’s third on 57 minutes.
It gave Arsenal their biggest away league win since beating Fulham 5-1 in October 2018.
Willian won the Premier League’s King of the Match award for his efforts.
Arsenal will next host West Ham on 19 September while Fulham will be heading away to Leeds United same day.