Chelsea manager Roberto Di Matteo explains why he wanted to sign Nigeria's Victor Moses from English Premier League rivals Wigan.
The European Champions League winners had four previous bids for the former England Under-21 international rejected.
No details were given on the contract for Moses, who played in the Blues' 2-0 victory at the DW Stadium on Sunday.
Chelsea are believed to have offered £7m up front, with a further £2m in add-ons.
Moses, 21, joined Wigan from Crystal Palace on a three-and-a-half-year deal in January 2010 for a reported fee of £2.5m.