Old Trafford, Mar 10: Danny Welbeck returned to Old Trafford as Arsenal booked a place in the FA Cup semi-finals at the expense of Manchester United.
The 24-year-old centre-forward returned as Arsenal's match-winner as the FA Cup holders sealed a semi-final place at Wembley.
England striker Welbeck joined Arsenal from United in a £16m deal on deadline day in September - and came back to score the goal that gave the Gunners their first win at Old Trafford since 2006.
It ensures Louis van Gaal, the manager who sanctioned Welbeck's sale, will almost certainly end his first season empty-handed.
Nacho Monreal gave Arsenal a first-half lead but Wayne Rooney equalised with a flying header from Angel Di Maria's cross - the high point of the Argentine's night as he was later dismissed for two yellow cards after Welbeck had restored Arsenal's advantage.
Louis van Gaal expressed his disappointment after Manchester United's FA Cup quarter-final defeat to Arsenal, saying the Reds "lost because of our own performance".
"We didn't lose to them, we lost [because of] our own performance, and that's very disappointing," the manager said at his post-match press conference. "The players are very disappointed; they know it could have been different.
"It's a pity because after we were 1-0 down, we recovered immediately."
"And the first chances of the second half were for us, so we could have decided the game,'' he added on MUTV.
Arsenal, who have now ended a run of 10 games at Old Trafford without a win, will face either Bradford City or Reading for a place in the FA Cup final.