5. Giovanni van Bronckhorst (from Arsenal, €2 million)-
The defender was seemingly doing well at Arsenal in the 2001-'02 and '02-'03 seasons, when he suddenly discovered the possibility of a loan move to Barca so as to work with their new Dutch manager, Frank Rijkaard. The move pulled through and the player found himself wearing the club colours for the first time in the most immediate league game itself.
A center-back player by default, Rijkaard had Bronckhorst switch to a left-back position instead, and the decision miraculously paid off. The next year, his transfer was made permament at €2 million, and Bronckhorst put his Arsenal days to shame while producing some spectacular moments with his new club on their way to winning the '04-'05 La Liga. "Gio" as he was fondly called and named on his kit, became an indispensable member of the first eleven soon after, as he helped Barca defend the La Liga apart from winning the UCL in 2005-'06. He was also the squad's only player to feature in all of the club's UCL run that season.
Until the end of the 2006-'07 season, Gio featured in 105 league appearances, also scoring five goals. He then returned to his boyhood club Feyenoord Rotterdam via a free transfer, where he spent the evening of his club career.