5) Sebastien Haller (Eintracht Frankfurt to West Ham – £45m)
The Ivorian was snapped up for a club-record fee from Frankfurt, after a season where he had bagged 20 goals in all competitions for the Bundesliga side.
However, Haller failed to impress during his 18 months in England, scoring just seven league goals in his first campaign for West Ham before being sold to Ajax in January for a loss of £25m.
