However, Arsenal were made to pay for their sloppy passing at the other end in the 44th minute, after Monreal gave the ball away needlessly in a unsafe area.
Arsenal were close to a second goal as they again exploited the space behind wing-back Cyrus Christie, with Henrikh Mkhitaryan's effort well saved by Marcus Bettinelli.
Arsenal took their lead back minutes after the halftime break when Lacazette scored his second goal of the match in the 49th minute.
"I am just thinking about the next match at the Emirates, with our supporters".
However, Arsenal looked a different team after the interval, with Lacazette scoring again before goals from Aaron Ramsey and Pierre-Emerick Aubameyang (2) sealed the win.
"We played very well, but we knew that Fulham play good football and would try to hit us on the counter-attack", the Gabon worldwide told BT Sport. The Gabonese worldwide, Pierre-Emerick Aubameyang was only among bench players in this game but he came on as a substitute in the second half to add two impressive goals to his goal tally this season.More news: Brewers fans wait in rain to welcome division champs home
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The win was Arsenal's sixth in a row in the Premier League after opening losses to Manchester City and Chelsea. We have a great team spirit, as you can see on the pitch.
Aubameyang and Ramsey had both been left on the bench, but Emery introduced them for the final half hour in a bid to kill off Fulham. We analyse the games a bit more and we're proving to the fans as well as ourselves that we're able to compete for the title.
Emery stated: "Yesterday he came in with pain and he can not train yesterday or play today".
"I believe in us, we believe in our process but also we must keep taking confidence". The Gunners faced a decent Fulham side in a Premier League clash. When we're winning now we need to be the same way in our mentality: calm, hard-working, enjoying working, failing together, sharing a feeling with our supporters.
'Today the players are playing, like Aaron Ramsey or Matteo (Guendouzi). They have the capacity to play lots of matches.