Javier Hernandez replaces Ole Gunnar Solskjaer as Manchester United's super-sub

Javier Hernandez has scored a league goal every 117 minutes for United, and one every 50 minutes this season. Eight of his 27 league goals have come as a substitute (Getty Images)

With his stunning performance at Aston Villa on Saturday, Javier Hernandez entered football folklore as one of the game's great substitutes.

Since 21 August 1965, when Keith Peacock of Charlton Athletic was the first replacement used in the Football League against Bolton, and Barrow's Bobby Knox became the first to score, against Wrexham, the concept of a hero coming off the bench to change the course of a game has become a romantic part of the football narrative.

Hernandez's appearances for Manchester United this season seemed destined to be less frequent, at least in the most important games, once Robin van Persie signed. But the pace he possesses is a more than useful quality for a substitute against tiring defenders, as demonstrated with his two goals in the 3-2 comeback win against Paul Lambert's side.

Hernandez of course has history as an impact player, first making his mark when coming on to score a late equaliser against Liverpool at Anfield in October last year.

Saturday's appearance was his 39th for United as a substitute, having made 55 starts; with Sir Alex Ferguson now promising that the 56th will be on Saturday at Norwich.

Ferguson has proved – as in many other areas of management – one of the most astute improvisers; most famously replacing Dwight Yorke and Andy Cole in the 1999 Champions League final with Ole Gunnar Solskjaer and Teddy Sheringham, who scored the last-minute goals that won the trophy.

In the days when Liverpool were still to be, in Ferguson's words "knocked off their f***ing perch", the ginger winger David Fairclough first earned the tag of "super-sub". His many notable contributions included the winning goal against St Etienne on one of the great Anfield nights, the second leg of the 1977 European Cup quarter-final. "He will never score a more vital goal," wrote Horace Yates in the Liverpool Daily Post.

Solskjaer already had a reputation as a man to make an impact even before his most famous goal in the Bayern Munich final. He eventually came off the bench exactly 150 times for United, as opposed to starting 217 games, finishing with 126 goals.

Hernandez left the Villa Park pitch holding the match-ball and claiming a hat-trick but the next meeting of the Premier League's dubious goals committee will almost certainly rule that United's second goal was put in by the Villa captain Ron Vlaar as he tried to block the Mexican's shot.

Asked if he was claiming the goal, Hernandez replied: "Of course. I shot on target, the defender tried to kick it away but he kicked it in the same direction I shot. I've just seen the replay and that was definitely hitting the target. But it doesn't matter who scored the goals. The most important thing is who is top of the league."

There was no doubt about his other two, however, which have given Hernandez a remarkable run of seven in the past five games.

Off the bench: who is the best?

Javier Hernandez Manchester United

Has scored a league goal every 117 minutes for United, and one every 50 minutes this season. Eight of his 27 league goals have come as a substitute.

Edin Dzeko Manchester City

Eleven of his 22 league goals have been as a substitute, with a goal every 64 minutes in the league this season. Half of his City appearances have been as a sub.