Chelsea's miserable form continued as Southampton came from behind to claim a deserved 3-1 victory over the champions on Saturday Night Football.

After falling behind to Willian's exquisite free kick on 10 minutes, Southampton produced a stunning comeback as goals from Steven Davis, Sadio Mane and Graziano Pelle sealed a first league victory at Stamford Bridge since January 2002.

The results leaves Jose Mourinho's men languishing in 16th place, 10 points adrift of Manchester City, who returned to the top of the Premier League with an emphatic 6-1 victory over Newcastle earlier on Saturday.

After clamouring among Chelsea fans, John Terry was reinstated into the starting line-up following his omission from their Champions League defeat at Porto.

Eden Hazard, Oscar and Radamel Falcao, in place of the suspended Diego Costa, completed four changes for Jose Mourinho's side, and the changes had the desired effect as the defending champions took an early lead.

Having scored in the three games prior, Willian notched his fourth goal on the bounce with a sumptuous free kick, looping a curling effort over Maarten Stekelenburg from wide on the right that cannoned in off the post.

Chelsea appeared to bask in the brilliance of the Brazilian's effort as they failed to build on their opener as Southampton began to grow into the game.

Southampton had two substantial claims for a penalty waved away by referee Robert Madley in the first half. First, Virgil van Dijk was tugged back by Branislav Ivanovic before Sadio Mane was clearly brought to ground by Ramires just after the half hour mark.

To rub salt in the wound, Mane was booked for simulation following a tackle by Ivanovic in the aftermath.

But the visitors were not to be denied and they drew level on 44 minutes as Pelle's skilful chest down set up Davis to rattle home the equaliser with a forceful volley.

The visitors took the initiative after the break and should have been in front when Mane was denied only by a smothering save from Asmir Begovic three minutes in.

Chelsea then had a strong claim for penalty turned themselves as Falcao - deputising for the suspended Diego Costa - was brought to ground by Stekelenburg.

There was clear contact but replays suggested the Colombian was on his way to ground beforehand. And within three minutes Southampton had the lead.

Tadic's inside pass was misread by Terry and allowed Mane through on goal, where he made no mistake in slotting the ball under the on-rushing Begovic.

The inclusion of Pedro did little to prevent a rampant Southampton side from getting their third on 72 minutes. Hazard's mishit pass handed possession to the Saints who broke though Mane. The Senegal international slipped Pelle in on the right and he hammered the ball beyond Begovic.

Half-time substitute Nemanja Matic was then hooked directly after the goal, with Loic Remy entering the fray as Chelsea tried to get back into proceedings.

But a comeback failed to materialise as Chelsea were condemned to their worse league start since 37 years, the season where they were relegated from the old First Division.

Click Here For Official Teamsheet

Player ratings

Chelsea: Begovic (8), Ivanovic (6), Cahill (6), Terry (6), Azpilicueta (7), Ramires (6), Fabregas (6), Willian (7), Oscar (6), Hazard (7), Falcao (6).

Used subs: Matic (5), Remy (4), Pedro (5).

Southampton: Stekelenburg (7), Cedric Soares (8), Fonte (7), van Dijk (7), Bertrand (7), Romeu (6), Wanyama (8), Mane (8), Steven Davis (8), Tadic (8), Pelle (8).

Used subs: Yoshia (2), Rodriguez (5), Ward-Prowse (6)

Man of the Match: Sadio Mane.

Teams

Chelsea Begovic, Ivanovic, Cahill, Terry (c), Azpilicueta, Ramires (Matic 45, Remy 73), Fabregas, Willian (Pedro 64), Oscar, Hazard, Falcao
Subs Not Used Blackman, Baba, Zouma, Loftus-Cheek
Booked Ramires, Falcao
Goals Willian, 10

Southampton Stekelenburg, Soares, Fonte (c), van Dijk, Bertrand, Romeu (Ward-Prowse 45), Wanyama, Mane (Yoshida 90+2), S. Davis, Tadic, Pelle
Subs Not Used K. Davis, Long, Martina, Juanmi
Booked Romeu, Bertrand, Mane, Tadic (Rodriguez 78), Ward-Prowse, Pelle
Goals S. Davis 43, Mane 60, Pelle 72

Attendance 41,642

Referee Bobby Madley