8. Sebastien Squillaci
Sebastien was shipped in from Lyon to solve Arsenal's rocky defensive issues, but did quite the opposite. Squillaci was unable to fit in and form partnerships with the likes of Koscielny, Mertesacker and Vermaelen, and ended up in the reserves for the most part of the last campaign before inevitably being released when his contract expired. The Frenchman was a relatively established name when Wenger signed him with 21 appearances for his country and spells at both Sevilla and Lyon on his resumé. He also has the honour of two Ligue 1 titles, a Copa del Rey and a member of Ligue 1 Team of the Year 2003-04 amongst others. In his first season at the Gunners, Sebastien played frequently and amassed 22 league appearances as well as appearing in 6 Champions League fixtures. However his performances came under heavy criticism after a multitude of high profile mistakes, and this is where it all went downhill. The following season, Squillaci appeared just once in the league and featured just a handful more in all competitions, and the subsequent season saw the French international play just one game, in the 2-1 defeat against Olympiacos in the Champions League. The risk of signing Squillaci seemed low at the time; already a well-known name and an experienced centre back to bolster Arsenal's backline, the low price needed for the Frenchman made this a no-brainer. Despite this it never quite worked out and Sebastien will be looking for a new club this summer, with a move back to Lyon a possibility. Though this is not the most disastrous on the list as Squillaci was a low cost player who simply could not make the starting 11, the fact remains that he was not a success and was at fault for a number of conceded goals at the Gunners. A loan spell or two in his last couple of seasons would have been handy, giving the player game time and keeping him fresh, but this was not the case.
Transfer fee: Around
£4 million.