Mesut Özil gave Arsenal the lead in the seventh minute at Emirates Stadium with a side-footed finish but the visitors drew level when Romelu Lukaku tapped in Ross Barkley’s cross before half-time.
It’s a difficult decision and possibly one you need to go in your favour
Mikel Arteta’s penalty then put Arsenal 2-1 up in the 68th minute, before substitute Olivier Giroud added gloss to the scoreline with two neat finishes.
But Toffees boss Martinez felt that Gareth Barry’s tackle on Alex Oxlade-Chamberlain was not a stone-wall penalty.
“I still think the penalty was soft but these key moments affect the game,” Martinez told ITV1.
“The key moment was the second goal. I feel it was a situation when Gareth Barry is fighting for the ball.
“Of course there is contact but is it enough to give a penalty? It’s a difficult decision and possibly one you need to go in your favour. It was always going to change the game and that was the case.”
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