The summer transfer window of 2021 might go down as the most memorable in history. A window which saw French giants PSG acquire Lionel Messi, Sergio Ramos, Achraf Hakimi, Genie Wijnaldum, and Gianluigi Donnarumma for just £54 million, Manchester City break the British transfer record by signing Jack Grealish for £100 million, and Shamrock Rovers …