Watch the best of the action as we extended our unbeaten run in the Premier League with a fine win at St Mary's.
The hosts went ahead early on with a thumping Stuart Armstrong volley from a corner, but we showed great resilience to turn it round and lead by the interval.
Nicolas Pepe slotted home the equaliser before Bukayo Saka rounded the keeper and scored from outside the box after being set up by Alexandre Lacazette.
Lacazette scored the third goal himself in the second half after we had absorbed a sustained spell of pressure from the hosts, as we leapfrogged Southampton in the table with our third straight away win in the league.
Click the 'Play' button above to watch a bitesize cut, while extended highlights and the entire first and second halves are available below.
Copyright 2021 The Arsenal Football Club plc. Permission to use quotations from this article is granted subject to appropriate credit being given to www.arsenal.com as the source.