#1 FC Barcelona

FC Barcelona had a poor 2017/18 summer transfer window. They failed in their pursuit of Marco Verratti from PSG and lost Neymar to PSG. They also signed Gerard Deulofeu who turned out to be a flop. Their only good thing was bringing Ousmane Dembele in.
This season, however, things have been very different. Barcelona managed to sell Paulinho to Guangzhou Evergrande for almost €50 million. They cleaned their benches of all the dead wood. Andre Gomes, Lucas Digne, Yerry Mina, all left for Everton.
Barcelona’s first summer signing was Clement Lenglet from Sevilla. They managed to get Arthur Melo earlier than expected, as he was scheduled to arrive in the winter originally. They followed it up with Malcom's signing and capped off the brilliant summer by bringing in Arturo Vidal.
Barcelona’s signings have been pinpoint. In Umtiti’s absence, Lenglet has shown why exactly Barcelona invested in him in the first place. He has been rock solid at the back, making important blocks in almost every game.
Arthur Melo has proven to be the controller that Barcelona so desperately wanted ever since Xavi left. Arthur has shown inspiring performances against Real Madrid, Inter and Tottenham, three top class sides. He was applauded when he was substituted against Inter.
Malcom hasn’t got much playing time thanks to an impressive showing from Dembele and Coutinho on the left wing, the right wing always has Messi. However, the Brazilian is a very good player as he proved with Bordeaux last season.
All the signings, with the exception of Vidal, are youngsters and will help Barcelona in the long term. Vidal brings in the physical dimension of play that Paulinho provided Barcelona with, only he has European experience and thus is better.
Barcelona has spent only about £115 million and they have landed world-class young players. Their summer signings have made a big impact. They are the ultimate winners in the 2018/19 summer transfer window.