Confidence wasn't high among the Goodison Park faithful ahead of the fixture, with a fan walkout even planned for the 27th minute of the game in reference to the club's 27 years without a trophy.
While that protest hardly led to empty stands as organisers would have hoped, it was still a sign of how disillusioned supporters have become with results and performances under boss Rafael Benitez.
It must have felt like more of the same was to come for the Toffees when forward Richarlison had a goal ruled out by VAR late in the first half, only for Martin Odegaard to fire the Gunners into the lead moments later.
VAR foiled Richarlison again just before the hour mark, chalking off a would-be equaliser for the most marginal of offsides.
The Brazilian eventually got himself on the scoresheet ten minutes from time, levelling matters - and drastically improving the mood among the home crowd.
The two teams appeared destined to take away a point apiece from the contest before Gray stepped up with an absolute rocket to snatch all three points for Benitez's men.
Arsenal goalkeeper Aaron Ramsdale has been in sensational form for the north London side this season. However, even he could do nothing except watch on as Gray's sweet strike from the edge of the box was past him in an instant, ultimately going in off the post.
Video: Demarai Gray's stoppage time screamer vs Arsenal
On balance, the late winner was nothing less than Everton deserved. With that said, it still came as a surprise to the home fans behind Ramsdale's goal - as Sky Sports' Jamie Carragher pointed out on Monday Night Football.
In the studio after the match, the former Liverpool defender singled out the lone Toffees supporter who realised that Gray was about to win the game for his side, while all around him stood motionless.
Everton 2-1 Arsenal - Gray scores superb stoppage time winner! (Via The Football Terrace)
"Look at the crowd. Nobody thinks it's going in," begins Carragher as he breaks down the replay.
"But there's one supporter who knows it's going in. He's maybe got the best view in the house.
"You knew was in lad, you knew it was," remarks Carragher, highlighting the supporter on-screen as Gray scores.
"Everyone else is not sure, but he knows before it goes in."
You can check out Carragher's unique post-match analysis below.
Watch: Epic fan reaction to Gray's winner gets Titanic treatment
One sure-fire way to know that a sporting clip is worth a watch is when it gets given the Titanic treatment - and the fan's reaction has already been set to the dulcet tones of Celine Dion.
In celebration of the superb clip, Carragher has even set the face of the fan concerned as his Twitter profile picture.
A fantastic reaction to a wonderful strike.
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