The Hammers surrendered a two-goal lead and missed a penalty as Thierry Henry and Sylvain Wiltord rescued a point in this fiercely contested thrill a minute derby.
"When you come back to 2-2 it feels like a victory," said a relieved Arsene Wenger after the game.
"You need special strengths to recover these situations but this team is exceptional and doesn't know when to give in."
Meanwhile, a disappointed Glenn Roeder said: "We had individuals out-performing Arsenal's internationals, it was a winning performance yet we've only taken a point. We've let Arsenal get away with it."
Commenting on Thierry Henry's fabulous strike, Arsene Wenger said: "It was amazing, like a missile. There wasn't even time to realise it was in and it wouldn't surprise me if it is one of the goals of the season."
Upton Park chief Glenn Roeder agreed, adding: "Very few strikers in the world can hit the ball as hard as that. It takes some shot to beat David from there. Sometimes, although you don't like to, you just have to put your hands up and say 'well done'."