The American put the Blues 1-0 up within five minutes after a delightful finish from Olivier Giroud’s lay-off.
Arsenal took control of the game after Chelsea’s goal and eventually got their chance to hit back when Cesar Azpilicueta pulled down Pierre-Emerick Aubameyang in the box.
The Gunners captain duly converted from the spot to get Mikel Arteta’s side back on level terms.
Azpilicueta shortly went off the pitch with a hamstring injury himself and was reduced to tears.
Minutes after the second-half began, Chelsea’s injury problems worsened as Pulisic also pulled his hamstring while running through on goal before he could get a shot away, ending his first ever FA Cup final early.
The 21-year-old has enjoyed an outstanding debut season for the Blues, registering nine Premier League goals and four assists.
He had a big job on his hands trying to fill to the void left by Eden Hazard and has already been likened to the Belgian stylistically.
Speaking of the comparisons between the two last month, Chelsea boss Frank Lampard said: ‘I don’t want to get involved in that one too much because I played with Eden.
‘They can both go by players and they’re great to watch.
‘Eden did it here and was sensational in what he did here with his input personally into the club winning trophies.
‘I don’t want to get on that comparison too much, but at the same time I don’t want to take away from Christian because what he’s showing now is a real natural ability, a balance and a speed to dribble with the ball.’
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