The Gunners took a first-half lead after Aaron Ramsey’s finished from close range before French midfielder Francis Coquelin was sent off early in the second half.
To come back from 2-1 with 10 men, here, with so much pressure, shows that they care and have heart
Tottenham defender Toby Alderweireld levelled against 10-man Arsenal five minutes after Coquelin’s dismissal before Harry Kane handed Tottenham a 2-1 lead two minutes later.
But Arsenal forward Sanchez restored parity in the 74th minute to secure a valuable point for Arsenal in the Premier League title race.
Former Tottenham midfielder Murphy was impressed with Arsene Wenger’s players for bouncing back from the sending off and home side’s quick-fire double.
“I think a draw is a fair result,” Murphy told BBC Sport.
“It would have been very hard on Arsenal to go away with nothing from this game. They started strongly and did really well to bring themselves back into the game.
“To come back from 2-1 with 10 men, here, with so much pressure, shows that they care and have heart.
“That result still leaves us no clearer as to who will win the league, but what an opportunity for Leicester later today.”
Arsenal are five points behind leaders Leicester City following Saturday’s north London derby.
Tottenham maintain their three-point advantage over the Gunners but could finish the day five points behind the Foxes.
Wenger’s side are in action against Hull City in their FA Cup fifth-round replay on Tuesday night.
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