Former Manchester United and England star Wayne Rooney was very certain when he was asked recently who his toughest opponent of all time was. In a time where Chelsea prepare for a new era under a new manager again in the form of Enzo Maresca, Rooney himself is preparing to return to the game in the role of boss at Plymouth Argyle. The former striker clearly has plenty of experience at the top of the game, and has faced some of the best defenders and midfielders that have ever been produced. However, it is a Stamford Bridge icon who he named his toughest opponent ever. Rooney names John Terry a…