Ninth-place Arsenal is five points behind fourth-place Chelsea. The victory means Arsenal has racked up three consecutive league wins for the first time in more than a year and manager Mikel Arteta was pleased with the impact of Lacazette, who has fallen behind Eddie Nketiah in the pecking order.
"Well, I have two strikers at the moment and they are making life difficult for me but at the same time it is very good," Arteta said. "They are both scoring, both in a good moment. I decided to play Eddie today for the defenders they had and the game plan we had, but knowing that Laca, if we needed a goal in the final moments, he was always ready to do that.
"I saw straight away, when I was talking to him and giving him instructions on the touchline, he was alert and focused and I could see he was really determined to go out there and score the goal that he did."
Arteta saw VAR rule in favor of Arsenal for the first time this season after Sian Massey-Ellis' decision to flag for offside, with the check deeming Angelo Ogbonna was playing Mesut Ozil onside. "When the goal was disallowed I thought, 'OK that's fine,'" Arteta said. "Then my staff came from the bench and said, 'It's a goal.' ... I am very pleased with the VAR tonight."
West Ham was unchanged from its victory over Southampton last weekend and created plenty of chances to win the game. Michail Antonio turned a close-range opportunity wide before seeing a free header kept out by Bernd Leno who impressed in the Arsenal goal.
The result leaves West Ham outside the bottom three by virtue of goal difference, with manager David Moyes bemoaning their lack of cutting edge. "We didn't deserve to lose it," he said. "In recent weeks we have made mistakes defensively that have cost us but today our mistakes came in that we didn't take the chances when we had them.
“That would be the disappointment but apart from that I thought the players did a great job, played very well and made several good chances but we couldn't convert them today.”
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