Chelsea's poor run under Graham Potter continued as Manchester City cruised to an emphatic 4-0 victory in the FA Cup third round.

Three days on from going down 1-0 to City in the Premier League at Stamford Bridge, Chelsea capitulated at the Etihad Stadium.

Riyad Mahrez's stunning free-kick, Julian Alvarez's penalty and Phil Foden's close-range finish had City all but through by half-time on Sunday.

A late Mahrez spot-kick provided the fourth as City look forward to a possible fourth-round meeting with league leaders Arsenal – who must defeat Oxford United to make that tie – while Chelsea showed little sign that immediate improvement under Potter is on the horizon.

Cole Palmer should have done better early on, but City did not have to wait long for their lead – Mahrez curling a brilliant free-kick into the top-right corner after being fouled by Lewis Hall 25 yards from goal.

Kai Havertz's desperate handball gifted City a chance for a second following a VAR check, and World Cup winner Alvarez's penalty snuck in under Kepa Arrizabalaga.

Mahrez was key to an exceptional third goal to put the tie to bed, sliding a perfectly weighted pass through to Kyle Walker, whose cutback was expertly turned home by Foden.

Chelsea had their first shot in the 55th minute, but Stefan Ortega was hardly troubled by Mason Mount's effort.

At the other end, Chelsea could not avoid further damage as Kalidou Koulibaly clattered into Foden late on.

Mahrez made no mistake from the spot, slamming high down the middle to cap a superb win and a miserable day for Chelsea, who exited in the third round for the first time since the 1997-98 season.

What does it mean? Free-scoring City the antithesis to Potter's blunt Blues

Chelsea's defending left a lot to be desired – albeit Potter elected to start youngster Bashir Humphreys in the backline – but their attacking play is equally concerning.

The Blues trailed by three goals at half-time for the second time under Potter in just his 18th game. They had never previously trailed by as many goals at the interval in any of Thomas Tuchel's 100 matches in charge.

While City's attack purred – Alvarez has been directly involved in 11 goals across his last 10 starts for club and country, and Foden became the only player to have scored in each of the past five FA Cup campaigns – Chelsea mustered an expected goals total of just 0.1 to their hosts' 2.7. Their issues are glaring.

Set-piece specialist Mahrez gives Chelsea the blues... again

After netting in Thursday's league win at Stamford Bridge, as well as the EFL Cup meeting between the teams earlier in the season, Mahrez started and ended the rout and in the process became the first player to score in three separate games against Chelsea in a single season in all competitions since Javier Hernandez for Manchester United 10 years ago.

His free-kick was a thing of beauty, and only James Ward-Prowse (13) and James Maddison (seven) have scored more direct free-kick goals for Premier League teams than Mahrez (six) since the start of the 2019-20 season.

Havertz has a stinker

With Pierre-Emerick Aubameyang not included in the squad after he was subbed on and then taken off in Thursday's loss, Havertz – the scorer of Chelsea's winner in the Champions League final between these teams in 2021 – was deployed up top.

He had a shocker. While he was starved of service, Havertz failed to have an attempt or create an opportunity and was dragged off at half-time after his rush of blood led to City's second.

What's next?

City visit Southampton for an EFL Cup quarter-final tie on Wednesday, while Chelsea face the task of bouncing back against rivals Fulham at Craven Cottage a day later in the Premier League.