The Gunners moved up to eighth in the table, albeit with other teams yet to play in this matchweek, and hit the 30-point mark as they extended their unbeaten Premier League run to six matches.
Goals from Nicolas Pepe, Bukayo Saka and Alexandre Lacazette sealed the win, with Arsenal fighting back after falling behind to an early goal from Southampton midfielder Stuart Armstrong.
While there were plenty of positives to take, there were two big injury concerns for Arteta with Manchester Unitd on the horizon.
Both Partey and Smith Rowe were forced off in the second half and will now face a race to be fit for Saturday evening’s clash with Ole Gunnar Solskjaer’s side.
He [Smith Rowe] was injured for the FA Cup game and we knew that probably today he could not play the whole game,’ said Arteta in his post-match press conference. ‘He had some muscular discomfort and had to come off again.
‘We had five players in the FA Cup that couldn’t play, [Kieran Tierney] was one of them and Thomas you could see not manage 60 minutes. We don’t know [if it was cramp]… but it was a struggle.’
Asked about Smith Rowe, Arteta added in an interview with BT Sport: ‘Well it’s one of the reasons why we had to make changes in the cup because we had five players who were not available to play.
‘I want to make that clear. The ones that played today they were to play some part of the game. ‘So we expect them to play every game of the season 50 games without preseason at that age I’m sorry but it’s impossible and I’m not going to do that with the young players.’
Saka was left delighted with the result, telling BT Sport: ‘It was much better than Saturday.
Saturday was disappointing. We are the holders [of the FA Cup] and we took it hard. We exploited their weaknesses and got the win we deserved.
‘I said to him (Lacazette) about the opportunity, saying I would run in behind. We got as goal so I am happy. I am not just happy with Laca, though, I am happy with everyone.
‘I am happy to be playing for Arsenal. I have the passion on the pitch and the boss gives me the freedom.
‘Game after game, we take it. We have to do that. The Premier League is changing rapidly this season. You have to focus on each and try to win