Cesar Azpilicueta and Juan Mata came in from the cold to net either side of half-time in a 2-0 Chelsea win - a result which means Wenger has now failed to overcome Mourinho in all their nine meetings.
The last encounter before tonight was the 2007 League Cup final, which the west Londoners won during a time in which the managers' relationship was far more fractious.
Those differences appear to have diminished over a time, with Mourinho's ire in the build-up instead focusing on the schedulers.
Initially threatening to field Chelsea's under-21 development side in protest of the match being little over 48 hours after the league clash with Manchester City, he eventually backed down in respect to Chelsea's fans.
The Portuguese still made 10 changes to Sunday's 2-1 win but all of those introduced were senior internationals, who were backed vociferously from the outset by 9,000 travelling fans.
Those supporters, like on Sunday, were grateful to a defensive mistake from their opponents. This time Carl Jenkinson was at fault, with Azpilicueta latching onto his poor back header to prod home midway through the first half.
Nacho Monreal almost levelled immediately and Aaron Ramsey came close on a number of occasions early in the second half, only for Chelsea to ensure the repeat of the final six years ago would go the same way.
Mata, still yet to prove himself indispensable to Mourinho, controlled the ball on the edge of the box and took a touch before unleashing a venomous right-footed strike, booking Chelsea's place in the fifth round.
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