Oxlade-Chamberlain’s lone strike was enough to power the Gunners to a win at the home of English football.
The 65-year-old Frenchman is now the most successful FA Cup manager of modern times.
After a nine-year trophy drought, Arsenal have now won the FA Cup two years in a row.
The previous schedule had the former host the veterans on June 3, followed by a June 7 kick off at Margao.
Sunderland’s American owner, Ellis Short, was in north London to see his team play out a goalless draw.
Chelsea have 84 points with two games to play, City have 76 with one to play.
Arsenal, who have 70 points from 35 matches, still boast a game in hand on City who are three points ahead.
Arsenal won the second leg but lost on away goal 3-3 aggregate against Monaco in the Champions League.
Manchester City’s title defense was dealt a further blow Saturday with a first loss to Burnley in 41 years.
One of their own, Welbeck came back to haunt United as he fired the winner on Monday at Old Trafford.
It was a night of upsets as two top teams were edged out in Champions League first leg.
Alex Oxlade-Chamberlain, however, will be out for another two weeks and Wenger had no date for the return of Jack Wilshere.
Lampard’s decision to stay with Manchester City has “outraged” fans of New York City FC.
Arsenal hang on to win in a tense finish after Giroud’s red card, remain within touching distance of top 4.
Despite failing to secure all 3 points, Arsenal moved back into sixth spot with 27 points from 17 games.
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