Christian Pulisic begins his first game of the season for the Blues this afternoon, while Kepa Arrizabalaga returns in goal for the visit of Southampton.
Pulisic’s start is his first since the FA Cup final back in August and the American joins an attacking unit also comprising Mason Mount, Kai Havertz and Timo Werner.
Kepa comes in for the injured Mendy, though Ben Chilwell is fit enough to start once again at left-back following an excellent Premier League debut last time out. Andreas Christensen for Thiago Silva is the only change to the back four, with Kurt Zouma and captain Cesar Azpilicueta retaining their defensive posts.
N’Golo Kante and Jorginho are the midfield pairing as there are four changes in total from our 4-0 victory over Crystal Palace last time out.
On Chilwell's inclusion, Frank Lampard said: 'His foot is okay. It might be something that is a bit of a longstanding one with him, as it won’t just clear up overnight. He had some pain in training this week, so we’re managing him in the short-term, but with the way he played in the last game and the way he’s shown himself in training in the past two days, he’s in the team. He looks sharp, he feels fit and he’s in today.'
Theo Walcott makes his second debut for the Saints 15 years after his first, in one of two changes from their 2-0 win over West Brom before the international break. Nathan Redmond’s return to the attack is the other. Former Blues Ryan Bertrand and Oriol Romeu both start on their return to Stamford Bridge.
Chelsea: Kepa; Azpilicueta (c), Christensen, Zouma, Chilwell; Kante, Jorginho; Mount, Havertz, Pulisic; Werner
Subs: Caballero, Tomori, James, Hudson-Odoi, Ziyech, Abraham, Giroud
Southampton: McCarthy; Walker-Peters, Vestergaard, Bednarek, Bertrand; Walcott, Ward-Prowse (c), Romeu, Redmond; Adams, Ings
Subs: Forster, Stephens, Valery, Tella, Diallo, Obafemi, Long
The referee is Peter Bankes
Frank Lampard’s side have won eight of our past nine games in all competitions at Stamford Bridge, seven with a clean sheet. Liverpool against a 10-man Blues in September was our only defeat in that run.
Since the start of 2019/20, no team (apart from the three promoted sides) have conceded fewer home Premier League goals than Chelsea (18 in 21 games).
Seventy-six per cent of our goals this season have come in the second half.
Olivier Giroud has had a hand in five goals (four goals, one assist) in his last four Premier League games against Southampton.
Southampton have won two of their last 11 Premier League away games in London (one being at Chelsea last season), losing seven.
Danny Ings was involved in every Premier League game for Saints last season and scored 43 per cent of the team’s goals. He has scored three of Southampton’s five league goals this season.
Ralph Hasenhuttl’s side have won eight of their past 13 away Premier League games in a run that started on 21 December.
Having lost their first two Premier League games this term to Crystal Palace and Tottenham, they have won the last two against Burnley and West Brom.
Southampton are hoping for a third successive Premier League win for the first time since May 2016 when they won four in a row when Ronald Koeman was in charge.
Southampton have faced 29 shots in the Premier League this season so far this season, fewer than any other side in 2020/21.