The 33-year-old former Real Madrid and Spain striker has revealed he turned down a personal plea from Sir Alex Ferguson to make the move to Old Trafford at the end of last season.
According to Spanish newspaper AS, Raul received a call from the Red Devils manager in June 2010, and although he was tempted by the offer, a move to Manchester United was not possible as he had already agreed a deal with Schalke.
Since his move to the Bundesliga outfit, Raul has continued to find the net, scoring 15 goals in 35 appearances this season, having forged a prolific strike partnership with Klass-Jan Huntelaar.
The ever-green Spaniard’s fine form has prompted further speculation that United will renew their interest again this summer, with Ferguson believing Raul’s experience will be a valuable asset in their continued pursuit of domestic and European glory.
In an illustrious Madrid career, Raul scored 323 goals for the Galacticos before finally calling time on his trophy-laden spell at the Bernabeau.
His move to Germany proved that the then ‘one-club’ man was prepared to move on in search of continued first-team football.
It is unclear at this stage however how much game-time Raul would be given if he opted for a move to Old Trafford in the summer.
With that in mind, Raul may favour extending his contract with Schalke, where he is regarded as an important first-team player rather than taking a step back and becoming a bit-part player for Manchester United.