Southampton came from behind to stun Chelsea 2-1 as Adam Armstrong's goal dealt Thomas Tuchel's men their second defeat of the Premier League season.

Chelsea hit the front through Raheem Sterling after 23 minutes, but Romeo Lavia's powerful long-range strike dragged Southampton level five minutes later before Armstrong put the hosts ahead on the stroke of half-time.

With Reece James missing through illness, Chelsea struggled to create throughout a disjointed performance, and Kai Havertz squandered their best chance to level after the break.

The result saw Ralph Hasenhuttl's men draw level with Chelsea in the early Premier League table after a lively display, as the Blues' unconvincing start to the campaign continued.

Sterling produced a tame attempt when presented with Chelsea's first chance 13 minutes in, but he made amends to hand the Blues the lead, turning to poke home at the second attempt following good work from Mason Mount.

Chelsea's lead did not last long, however, with Lavia latching onto Havertz's clearance to open his Premier League account in spectacular fashion by drilling a vicious 18-yard strike past Edouard Mendy.

Southampton then hit the front through a well-worked goal as half-time approached, Armstrong controlling Romain Perraud's cross before composing himself and firing into Mendy's top-left corner.

Marc Cucurella kept Chelsea in the contest with an incredible goal-line block from Mohamed Elyounoussi's header after the break, before Havertz headed over from six yards when left unmarked as he met Cesar Azpilicueta's cross.

That represented Chelsea's clearest opportunity to find a leveller, with Thiago Silva forced to clear Mohammed Salisu's 73rd-minute header off the line as Saints went close to a third.

What does it mean? Away-day blues continue for Tuchel

Chelsea never looked entirely comfortable on the south coast despite taking an early lead, and the meek loss means they have lost consecutive Premier League away matches for the first time since December 2020 under Frank Lampard.

Tuchel, meanwhile, has been dealt his first back-to-back league losses on the road since he was coaching Paris Saint-Germain in August 2019, and his attentions will now turn to attracting much-required reinforcements before the transfer deadline.

Sterling shows his value

Having fired Chelsea to a hard-fought victory over Leicester City last time out, Sterling maintained his strong start at Stamford Bridge by opening the scoring.

Since Sterling made his Premier League debut for Liverpool in March 2012, he has 169 goal involvements in the competition, putting him level with Mohamed Salah with the joint-fourth highest tally in that time.

Armstrong ends drought

Armstrong had endured a long wait for a Premier League goal, with his composed strike marking his first time on the scoresheet in 18 games since he netted against Aston Villa last November.

The striker has only scored three times in 43 appearances in the competition overall, and Tuesday's strike is sure to be remembered as his most crucial to date.

What's next?

Chelsea welcome West Ham to Stamford Bridge for a London derby on Saturday, while Southampton go to Wolves on the same day.