The Polish international spoke to the club's website after the 5-2 home defeat to his former team in what was his 207th appearance for the club.
“For all of us, it’s a very disappointing afternoon,” said Fabiański.
“It’s actually quite hard to describe the performance. We were up against a good side, who played well, but we definitely feel we could have done better so it is frustrating.
“We were all aiming to start strongly - our target was to be on the front foot, to press high and be in possession of the ball. But we made some sloppy mistakes, and Arsenal punished us.”
His challenge on Gabriel was deemed a penalty as Buyako Saka fired Arsenal’s fifth goal into the back of the net. Fabianski said he was focused on nothing but the ball but admitted he wants to put the game behind him and focus on Leicester City this week.
“He (Gabriel) outjumped me,” the 39-year-old said. “I tried to reach the ball, but he came from the blind side. I was always focused on the ball, but I think he came from a stronger position because I was jumping from standing.
“It’s a disappointing day, but there is another game in a few days and we will be focused on responding well in Leicester. Hopefully we can come back from there with a result.”
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