We look at five previous occasions where two Premier League clubs have been involved in player exchanges (including cash) and how those players fared at their new clubs.
During seven-and-a-half seasons at Man Utd, Cole scored 93 goals in 193 Premier League matches and won five League titles.
Gillespie helped Newcastle United finish second in 1995/96 and 1996/97, as well as reach the 1998 FA Cup final. He made 113 PL appearances for Newcastle, scoring 11 goals.
The two strikers did not have immediate impacts at their new clubs.
After an injury-disrupted start, James Beattie enjoyed his most prolific Premier League season on the south coast in 2002/03, netting 23 goals.
Overall, he scored 68 goals from 204 Premier League matches for Southampton.
Appointed captain at Emirates Stadium in his second season, William Gallas netted the winner against his former club in December 2007, one of 11 Premier League goals from 101 appearances.
Joining Cardiff City for the second half of the 2013/14 season, Kenwyne Jones struggled in front of goal, scoring just once in 11 Premier League matches as the Welsh side battled in vain against relegation.
Peter Odemwingie fared better initially, getting five goals for Stoke City in 2013/14. But he was unable to score again in the Premier League for the Potters as injury blighted his stay there, making 27 PL appearances overall.
Michel Vorm has had more difficulty getting selected ahead of Hugo Lloris in the Spurs goal, making just 11 PL appearances.