Robin van Persie returned to the Emirates Stadium to deny his former club a vital win on Sunday.
The Dutchman found the net with a late first-half penalty as Manchester United came from a goal down to earn a 1-1 draw in North London in the Premier League.
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Theo Walcott had earlier opened the scoring with a controversial strike on three minutes.
The result leaves the Gunners fourth in the Premier League table, two points above rivals Tottenham Hotspur, who have a game in hand.
It also means that United cannot beat Chelsea's record haul of 95 Premier League points, which the Blues set in 2005.
Arsenal started the game on the front foot and they deserved their early lead, although Walcott's effort should have been ruled out for offside.
However, the flag stayed down, allowing the England forward to latch onto Tomas Rosicky's through-ball and finish clinically from eight yards.
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United came close to levelling on the quarter-hour mark, but Phil Jones headed just wide following a brilliant run-and-cross by Van Persie.
Van Persie was then thwarted by an incredible point-blank save from Wojciech Szczesny, who blocked the Dutchman's close-range header with his face.
However, Van Persie was not to be denied in the final minute of the first half.
Bacary Sagna played a slack back-pass, which Van Persie pounced upon before being hacked down by the French full-back, leaving referee Phil Dowd with no choice but to point to the penalty spot.
Szczesny dived the correct way, but the Dutchman's effort was too good.
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The second half was a much more low-key affair, but United still managed to create two glorious chances.
Szczesny made a vital block from Wayne Rooney's header on the hour and then Ryan Giggs almost won the game in stoppage time, but his low effort deflected just wide.
United were shown five yellow cards, as Jones, Van Persie, Jonny Evans, Rafael da Silva and Antonio Valencia all entered Dowd's notebook.
The last time that the Red Devils received five bookings in one game was in the reverse fixture against the Gunners in November.
Robert Summerscales
