PEPE THE PENALTY KING
It was a big call for Pepe to step up and take the penalty at 1-0 down. Our record signing was playing his seventh game for us, still looking for his first goal, so he was under a certain amount of individual pressure himself, regardless of the match situation.
Pierre-Emerick Aubameyang was our regular spot-kick taker last season, and with six goals already to his name so far this campaign, one could have expected him to take the ball after Matteo Guendouzi was hauled down. But Unai Emery revealed after the game that Aubameyang is still the designated penalty taker, and that it was the top scorer's decision to help get his striking partner off the mark.
Not that the Ivory Coast international is any stranger to scoring from 12 yards. He was the regular penalty king at previous side Lille – he scored nine times from the spot in last season's French top flight alone. In fact no player has converted more penalties than Pepe since the start of last season in any of the top five European leagues.
His composure didn't desert him on this occasion either, thumping home left-footed past Tom Heaton to trigger the comeback.
It's certainly no reflection on Saka's performance over the opening 45 minutes that he was withdrawn at half-time. It was a change borne of necessity, after Ainsley Maitland-Niles's red card - the teenager was the unlucky one to be sacrificed for an extra defender.
It was a disappointing way for the exciting forward to end his first ever Premier League start, coming just three days after his man-of-the-match performance in Frankfurt.
By being named in the starting XI on Sunday – one of five players to retain their place from Thursday's win – the 18-year-old became our third youngest ever full Premier League debutant, only beaten by Cesc Fabregas and Theo Walcott.
And he looked set to make the most of it from his left-wing position, swinging in an inviting cross for Ainsley Maitland-Niles after just two minutes. A fizzing 20-yard shot, this time with his right foot, that needed to be tipped just over, was another highlight.
His only previous Premier League experience was a seven-minute cameo in last season's 4-1 home win over Fulham, but he already looks well at home at this level, and next time, he will hopefully get longer to prove it.
CHAMBERS TO THE RESCUE
Saka's misfortune though was Calum Chambers' gain. The defender was brought on at half-time to restore balance to the back four after Granit Xhaka had filled in at right back for the final five minutes of the first-half.
But with Arsenal chasing the game Chambers knew he would have to contribute in an attacking sense too, which he did in some style to grab our second equaliser.
It was only the defender's fourth goal for us (all at the Emirates) but it was taken like a seasoned finisher. From then on, the momentum was well and truly with us.
After the disappointment of losing a two-goal lead at Watford last weekend, it was a huge fillip for the team to turn the tables against Villa, fighting back not once but twice with a spirited second-half display.
The last time out at Emirates we came from two down to draw with Tottenham, and we showed our resolve once again here, roared on by the home crowd.
It was only the ninth occasion in Premier League history that a team has won after being behind and then being reduced to 10 men. Two of the previous wins have also been by Arsenal, most recently 11 years ago at Bolton.
It's also the third time in the past six matches that we have gone on to win after conceding the first goal.
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