Arsene Wenger made 11 changes at the City Ground, with Perez scoring twice, once from the spot, for his first goals for Arsenal.
Xhaka opened the scoring, finding the net from long range for the second successive appearance, while Alex Oxlade-Chamberlain (£6.0m) completed a comfortable evening for the Gunners.
With Olivier Giroud yet to start up front for Arsenal this season, Perez's brace made a case for his second start of the campaign, against Chelsea on Saturday evening.
Philippe Coutinho (£8.1m) played a part in all Liverpool's goals in a 3-0 EFL Cup win over Derby County that can only have made the Reds more tempting for FPL managers ahead of their Gameweek 6 match with Hull City.
Owned by 28% of FPL managers, Coutinho's assist in Liverpool's 2-1 win at Stamford Bridge in Gameweek 5 provided his first attacking points since the opening weekend.
Coutinho teed up Divock Origi (£6.7m) for the third as Liverpool look to be building momentum for a kind run of upcoming fixtures, starting with Hull at Anfield.
Fabregas, who has played only 35 minutes in the Premier League this term, also assisted Cahill’s goal.
Ronald Koeman made six changes from the Everton side who beat Middlesbrough last weekend, with Romelu Lukaku (£9.3m) given the night off as he recovers from a minor toe problem, but saw Norwich City end his unbeaten start at Goodison Park.
Lewis Grabban (£4.5m), who has yet to start in the league this season, was on the scoresheet for the first time as a much-changed AFC Bournemouth exited the competition, losing 3-2 at home to Preston North End after extra-time.