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May d best team lose
Betting tips: 15min draw
Lets go there
Chelsea's Ben Chilwell is fit despite withdrawing from England duty, but Edouard Mendy misses out after injuring his thigh in training with Senegal.
Thiago Silva will be rested, while Christian Pulisic and Hakim Ziyech could both feature, with the latter in contention for the first time.
Theo Walcott could play his first game for Southampton since 2006 after rejoining the club on loan.
Another new signing, Ibrahima Diallo, is available for his debut.
Moussa Djenepo and Mohammed Salisu are both ruled out, while Stuart Armstrong will not be considered, although he is back in training after a period of self-isolation following a positive coronavirus test.
Chelsea's new players are finding their feet and right now it feels like teams will get opportunities against them.
Southampton have won their past two games after a sticky start to the season, and I am sure they will have their chances on Saturday too. I would still back the Blues to win, though.
Chelsea lost 2-0 at home to Southampton last season but have won seven of the past nine league meetings (D1, L1).
Southampton could record back-to-back away league wins against the Blues for the first time since 1985.
Chelsea have not conceded a Premier League home goal against a side from outside the established top six since losing 2-0 to Southampton last December.
The Blues have won seven of their past eight league games at Stamford Bridge, scoring 18 goals in total and conceding just four.
They could keep a clean sheet in consecutive top-flight matches for the first time under Frank Lampard.
Olivier Giroud has scored seven league goals against Southampton, with each of the last four coming as a substitute - the only player to have scored five Premier League goals against a particular opponent from the bench is Julian Joachim versus Derby.
Southampton can claim three consecutive league victories for the first time since winning their final four games of the 2015-16 season under Ronald Koeman.
They could also record three successive top-flight clean sheets, a feat they last achieved between September and October 2016.
Saints have collected 20 points away from home in 2020 - only Liverpool have fared better.
Danny Ings has scored 13 Premier League goals in 2020, a tally exceeded only by Mohamed Salah.
Let's go boys.
Kepa please if you are the one between the sticks for Chelsea, try your best. No errors please
Blue is the colour.
A win is expected.
Match kick off
DOUBLE SAVE! Huge chance for Chelsea to take the lead through Chilwell and then Havertz!
Chilwell has acres on the left, found by Mount, and his low shot for the far corner from 20 yards is beaten away by McCarthy, but it's straight to Havertz...
He has a fierce attempt at goal, but it's too central, and McCarthy beats it away again!
Fantastic goalkeeping, but a worrying amount of space for Chelsea to exploit there.
SAVE! Now a chance for Saints! This is where the high press works.
Walcott and Adams interchange nicely, Walcott is fouled on the edge but advantage is played as Adams has a clear shot at goal, but Kepa is there to block with his foot!
Good chance from 15 yards, in space!
BALL IN THE NET! Werner denied his first PL goal!
Chilwell sticks in a delightful ball from the left, Werner gets across the front post, heads towards goal, and McCarthy gets a touch but can't keep it out!
However, the flag is up, and rightly so. He's a foot or so off.