Unai Emery’s men have now won 15 consecutive Premier Leagues at Villa Park and back-to-back victories over Manchester City and the Gunners have sparked hopes of an unexpected challenge for their first title since 1981.
The only goal came after just six minutes when Villa captain McGinn span onto Leon Bailey’s cross and fired into the top corner.
“What a monumental week it has been for us,” said McGinn.
“That was actually a really tough spell for us we played Thursday, Sunday, Wednesday, Saturday and I think it showed in our performance tonight, it wasn’t our best, but I’m certainly not complaining.
“The second half was a bit of character, a bit of grit and fair play to the substitutes who’ve come on. A couple of them haven’t played for a long time who dug right in there.”
Arsenal’s second league defeat of the season leaves Mikel Arteta’s men one point behind Liverpool, who went top with a controversial 2-1 win at Crystal Palace earlier on Saturday.
Victory was sweet for Emery, who was sacked by Arsenal four years ago.
The Spaniard has made a remarkable impact in just over a year at Villa on his return to England.
Arsenal’s ascent to the top of the table prior to this weekend has been built on a series of vital late goals.
And the visitors nearly snatched a point in stoppage time as Kai Havertz forced the ball home in a goalmouth scramble, but the German international handled before prodding in at the back post.
Arsenal were left to rue a big early missed chance from Bukayo Saka as he failed to make contact with Gabriel Martinelli’s cross.
Seconds later, they were behind as McGinn took a perfect touch from Bailey’s cross to tee up his fifth goal of the season.
Emiliano Martinez ensured Villa’s lead lasted until the break as he denied Martin Odegaard and Gabriel Jesus.
Arteta was forced to watch from the stands as he served a touchline ban and it was a frustrating watch for the Arsenal boss as Villa rode their luck in the second half.
Ollie Watkins turned a corner onto his own post before Odegaard wasted another big chance by skewing wide.
Saka did finally find a way past Martinez, only to be flagged offside.
And there was late drama when Havertz outmuscled Matty Cash to bundle in at the back post.
The ball appeared to come off both players’ hands as they battled for possession, but the referee’s decision to award handball against Havertz was confirmed after a lengthy VAR review.
Arsenal’s defeat opens the door for fourth-placed City to close back to within four points of the top when the English and European champions visit Luton on Sunday.
