Charlie Austin gave Ralph Hasenhuttl his first victory in charge of Southampton and ruined Arsenal's 22-game unbeaten run with an 85th-minute winner in a 3-2 triumph on Sunday.
Danny Ings and Henrikh Mkhitaryan both hit braces before Bernd Leno came and missed Shane Long's cross to allow substitute Austin to head the hosts to their first victory in 15 outings.
5 - Charlie Austin has scored in all five of his Premier League games against Arsenal - only Raheem Sterling versus Bournemouth (6 games) has a better 100% record of scoring against a specific opponent in Premier League history. Routine.— OptaJoe (@OptaJoe) December 16, 2018
Much of the build-up centred on the role Laurent Koscielny, starting his first top-flight match since April, would play in stabilising a makeshift three-man defence, yet it was he who twice lost Ings for a pair of first-half headers.
Mkhitarayan replied with one of his own before the break and levelled for the second time with a deflected 53rd-minute shot, but the Gunners' second-half fightback stopped short on this occasion as they were left three points adrift of the top four.