WATCH: Manchester United forward Alejandro Garnacho punishes Man City in FA Cup final with opening goal after disastrous defensive mix-up

Manchester United youngster Alejandro Garnacho capitalized on a defensive error from Manchester City to give the Red Devils the lead in the FA Cup final.

Garnacho struck in the 30th minute before Kobbie Mainoo made it 2-0 in the 39th minute. The Argentine capitalized on a disastrous mix-up in the City defense.

Ederson came on the edge of his box to deal with a long ball. However, he was caught up in a no man's land. Josko Gvardiol tried to head the ball towards Stefan Ortega. However, his header looped over the Brazilian goalkeeper.

Garnacho had the goal at his mercy and made no mistake in finding the empty net. He became the first teenager to score in the FA Cup final since Cristiano Ronaldo in 2003-04.

Watch Alejandro Garnacho's goal:

Manchester United have since doubled their lead with Kobbie Mainoo striking nine minutes later. They built up expertly before Bruno Fernandes played an exquisite pass to find Mainoo. The youngster scored from close range and United now have two teenagers scoring to give them a two-goal cushion.

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Alejandro Garnacho has been crucial for Manchester United this season

Alejandro Garnacho has been a key player for Manchester United this season. He has become a mainstay in the first XI under Erik ten Hag.

Garnacho has returned the favor to the Dutch manager with his on-field performances. He has scored 10 goals and has provided five assists in 50 appearances across competitions this season.

Garnacho's goal could very well prove to be pivotal in United's pursuit of the FA Cup. City, however, still have time to recover in the game.

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