Whatever United's predicament on and off the pitch, Rooney is the Red Devils' man for all seasons.
Despite his numerous honours and status, the 24-year-old England striker's enthusiasm for all aspects of the game remains as strong as ever.
He scored four goals but could have had more. And there was no player on the pitch who covered more ground than Rooney.
His first goal came in the eighth minute. Ji-Sung Park found Paul Scholes 25 yards out and the United veteran fired in a stunning shot.
Hull goalkeeper Boaz Myhill parried the effort, but Rooney was on hand to collect the rebound and bury his right-foot shot into the net from eight yards.
Rooney had to wait a further 74 minutes before bagging his second goal.
Nani hit a viciously swerving free-kick from 25 yards which was spilt by Myhill.
The Hull goalkeeper managed to bundle the ball onto the bar and then barged into defender Andy Dawson as he attempted to atone for his error.
Hull failed to clear effectively and Nani found Darron Gibson, who touched the ball to Rooney and he scored with a right-foot shot from 12 yards.
Rooney was now in unstoppable form and completed his hat-trick four minutes later when he met Nani's deep cross from the right to send his bullet header into the net at the far post from eight yards out.
Rooney notched his first four-goal haul for the Red Devils three minutes into injury time when he collected Dimitar Berbatov's clever flick from the left side of the Hull penalty area and turned his shot from 12 yards in between two defenders and into the net.
Michael Owen missed two good chances to score for United, while Rooney, whose goal tally is now 20 for the for season, could have had more.
United goalkeeper Edwin van der Sar made competent saves from Nicky Barmby after 18 minutes and Kevin Kilbane from the last kick of the game, but nothing could have overshadowed Rooney's brilliant display.