3) Alberto Aquilani (Roma to Liverpool – £18m)
The Italian was seen by Rafa Benitez as Xabi Alonso’s successor after the Spaniard was sold to Real Madrid, but injuries effectively ended the midfielder’s Anfield career before it started.
Aquilani arrived with an ankle injury and struggled to come to terms with English football when he did make his first-team debut. After just one season, he moved to Juventus on loan before another year in Italy with AC Milan. The midfielder was then sold to Fiorentina for just £1.8m in 2012.