London: Arsenal bounced back from their shock defeat by Birmingham City in the League Cup final when Denmark striker Nicklas Bendtner scored a hat-trick in a 5-0 demolition of Leyton Orient in the FA Cup on Wednesday.
The victory set up a quarterfinal visit to Manchester United.
Manchester City also reached the last eight with an emphatic 3-0 win over a much-changed Aston Villa team and they face Championship side Reading, who beat Premier League Everton on Tuesday, in the last eight.
Arsenal, held 1-1 by league one Orient in the first match of the fifth-round tie, were looking for a response after losing to Birmingham and had the game wrapped up by halftime with two goals from Bendtner and one from Marouane Chamakh.
Bendtner completed his hat-trick with a 62nd-minute penalty and Gael Clichy fired home the fifth with an angled left-footed drive after 75 minutes.
City took an early grip at Eastlands when Yaya Toure opened the scoring with a close-range goal after Villa failed to clear a corner in the fifth minute.
Mario Balotelli added the second before David Silva completed the scoring 15 minutes from time.
The other quarterfinals are Stoke City against West Ham United and Birmingham against Bolton Wanderers.