The identity and position of the player is to be kept a secret, but the Blades boss did say that he enjoyed every minute of the match action.
Regardless of which league the Blades will be playing in next season (Premier League or Championship) the United manager will be looking to strengthen his squad for the 2007-08 campaign.
"It's been worthwhile," Warnock told the Sheffield Star "It was a good game and an interesting experience.
"One of the teams was having a real go and the other was hanging on for dear life at times but really dug in and stuck to their cause.