Following a bit of a stuttering start to the campaign, Saints burst into life in the season's second month.
There were positive signs in their first game of September, away to Arsenal. Petr Cech's own-goal, after Dušan Tadić's superb free-kick hit the bar and bounced off the Gunners keeper, put Saints ahead.
They looked on course for at least a point, after Laurent Koscielny quickly cancelled that goal out, but an extremely controversial penalty for an alleged José Fonte foul on Olivier Giroud allowed Santi Cazorla to convert a 90th-minute spot kick.
Still, Saints took their encouraging performance and built on it five days later, as they thumped Sparta Praha 3-0, at St Mary's, in their opening Europa League game – Charlie Austin scoring twice, before Jay Rodriguez added the third late on.
Austin was again on target a few days later, as he hammered home the only goal of the game to secure a 1-0 home win over Swansea and a first Premier League victory of the campaign.
Three days later, Saints were back at St Mary's again, for what would prove to be the start of an incredible EFL Cup run.
Crystal Palace were first up for them, with Austin netting a first-half penalty before young Jake Hesketh scored his first senior goal in the second half to give Claude Puel's side a 2-0 win.
Saints then bagged a first away success of the campaign, as they went to West Ham and won 3-0 in the Premier League.
Austin's clever finish from Ryan Bertrand's cutback sent them on the way, before the striker set up Dušan Tadić to exquisitely dummy his way past the keeper and make it 2-0. James Ward-Prowse's late goal then completed the emphatic result.
A busy September then concluded with a long trip to Israel, as Saints toughed out a 0-0 draw against Hapoel Be'er Sheva to maintain their unbeaten start to the competition.
Saturday 10th Arsenal (a) L 1-2
Thursday 15th Sparta Praha (h) W 3-0 (Europa League)
Sunday 18th Swansea City (h) W 1-0
Wednesday 21st Crystal Palace (h) W 2-0 (EFL Cup)
Sunday 25th West Ham United (a) W 3-0
Thursday 29th Hapoel Be'er Sheva (a) D 0-0 (Europa League)