Arsenal responded well, though, and Aubameyang brought them level with his sixth goal in eight appearances for the Gunners as he flicked home Welbeck’s pass.
Welbeck put Arsenal ahead seven minutes before the break when he accepted a pass from Alex Iwobi on the left and shrugged off challengers before unleashing a shot that was helped past McCarthy by a deflection off Maya Yoshida.
The second half began with McCarthy making impressive saves from Aubameyang, Granit Xhaka and Iwobi to underline why he is keeping England international Fraser Forster out of the Southampton team.
At the other end Elneny had to head off the line to keep out Wesley Hoedt’s header and Cech dived to save another Long effort.
FULL TIME: #Arsenal 3-2 #SaintsFC
A battling display but it’s the hosts who take all three #PL points, with both sides reduced to ten men late on. pic.twitter.com/80JFvn2bZb
— Southampton FC (@SouthamptonFC) April 8, 2018
Long had the ball in the net from Saints’ next attack, deflecting in a long-range effort from Cedric but the forward was marginally offside, even if he didn’t think so.
An equaliser was coming, though, and was netted by substitute Austin the 73rd minute after Cedric had burst into the box to square the ball for a tap in.
Welbeck missed a great chance to put Arsenal back ahead when he fired over from three yards out after Wilshere had hooked the ball across goal.
But the England international made no mistake nine minutes from time when he headed Iwobi’s delivery to the back post beyond McCarthy.