Christopher Nkunku scored a hat-trick as Chelsea thrashed fourth-tier Barrow 5-0 to reach the last 16 of the League Cup on Tuesday as a much-changed Manchester City edged out Watford 2-1.
Nkunku now has six goals in seven appearances this season, but the Frenchman has still been unable to nail down a regular place in Enzo Maresca's side.
Maresca made 11 changes from the team that beat West Ham 3-0 on Saturday but could still start around £400 million ($533 million) worth of talent.
Joao Felix was another of the Blues' big-money signings to shine. His scooped pass set up Nkunku for the opener.
Nkunku then flicked home a second before Felix's free-kick hit the post and rebounded in off Barrow goalkeeper Paul Farman.
Pedro Neto tapped in Mykhailo Mudryk's cross for his first Chelsea goal. Nkunku sealed his first hat-trick for the club when he dispossessed Farman and rolled into an empty net.
City began what is likely to be many months without key midfielder Rodri after he suffered suspected knee ligament damage in a fiery 2-2 draw against Arsenal in the Premier League on Sunday.
Little over 48 hours on from that top-of-the-table clash, City were in action again and Pep Guardiola made nine changes, including a debut for 16-year-old Kaden Braithwaite.
Jeremy Doku, one of the two to retain his place, fired in the opening goal from Jack Grealish's pass after five minutes.
Rodri's absence could mean a more prominent role for Matheus Nunes and the Portugal international blasted in his first goal since joining City for £53 million a year ago.
Tom Ince, son of former Manchester United midfielder Paul Ince, pulled a late goal back for Watford, but it was too little, too late for the Championship side.
Aston Villa's second string were also pushed by lower-league opposition but Emi Buendia's header and Jhon Duran's penalty were enough to win 2-1 at Wycombe.
CLOSE TO AN UPSET
Fourth-tier Walsall came closest to an upset as they forced Leicester to penalties after a 0-0 draw.
However, the Premier League side won the shoot-out 3-0.
Newcastle's trip to AFC Wimbledon was postponed after a sinkhole appeared on the League Two side's pitch following heavy flooding in London this week
The match has been switched to Newcastle's St. James Park on October 1.
Newcastle have contributed £15,000 to a fund to help repair the pitch at Cherry Red Records Stadium.
Manchester United and Tottenham were among the sides to progress to round four last week.
Liverpool take on West Ham and Arsenal host Bolton in the remaining two ties on Wednesday.