Alejandro Garnacho has already made Manchester United's decision for him

In the dying embers of the FA Cup semi-final, Erik ten Hag looked over to his bench to see what he could change. Manchester United were lifeless and leggy for much of the match against Brighton, yet the manager was reluctant to bring on fresh legs just for the sake of it.

Anthony Martial only lasted until the 85th minute because, quite frankly, there were no other viable options at United's disposal. Antony was replaced in added time when it became abundantly clear he would not be the match-winner they had hoped for.

Taking off Bruno Fernandes and replacing him with Wout Weghorst looked akin to Louis van Gaal's infamous decision to replace Juan Mata with Nick Powell in their Champions League exit to Wolfsburg back in 2015. This time, the gamble paid off.

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United's penalty shootout success vindicated those decisions, though the underlying worry is that they will most likely need to offer a lot more when they face fierce rivals Man City in the final.

It was a day in which they were crying out for a gamechanger from the bench. Someone to run at a tired defence, with enterprise and energy. They needed Alejandro Garnacho.

The 18-year-old is still an incredibly raw talent but has showcased this season he has the tenacity and talent to grab a game by the scruff of the neck. Garnacho registered four goals and five assists in 29 appearances prior to his ankle injury last month. He also boasts an impressive four goals in four appearances for Argentina's U20s.

While he still has a lot of work to do, his youthful innocence and pure persistence make him a thorn in the side of many opposition defences. Most players drop their heads when they lose