Introducing the right player at the right moment can completely change a game of football. And, when Javier Hernandez came off the Manchester United bench to rescue a 3-2 victory against Aston Villa at Villa Park on Saturday, it emphasised the importance of the Premier League super-sub.
The 24-year-old striker's second-half brace took his tally to seven goals in his past five appearances, with Chicharito's goalscoring exploits drawing comparisons with United's greatest ever impact player, Ole Gunnar Solskjaer.
To this day, the Norwegian remains the Old Trafford club's most celebrated super-sub, with 28 goals from Sir Alex Ferguson's bench, including that historic 1999 Champions League final winner against Bayern Munich.
Hernandez is now closing in on Solskjaer's record, and currently lies on 16 Manchester United goals as a substitute. In the space of three weeks, his contribution has clinched the Red Devils' qualification for the Champions League knockout stage with victory at Braga, and helped secure six points in the title race with victories at Chelsea and Villa.
The Mexican is not alone when it comes to significant substitutes, though, as Edin Dzeko proved once again with his match-winning effort for Manchester City in Sunday's 2-1 victory over Tottenham at the Etihad Stadium.
He too is building a reputation as an influential fringe player for Roberto Mancini's reigning champions, scoring six of his seven goals this season from the bench, making him City's top scorer, despite having played a fraction of the game time of Carlos Tevez and Sergio Aguero.
Here GiveMeFootball celebrates the under-appreciated role of the Premier League super-sub, and picks out some of the best still plying their trade in the top-flight today…
Michael Owen | Stoke City
Injury problems continue to halt the former Manchester United striker's progress at the Britannia Stadium, but Tony Pulis will know that Owen's experience is invaluable for his squad, and when on the pitch he is always going to be a threat on goal.
Jermain Defoe | Tottenham
Traditionally a great impact player, Defoe has already seen more action for Spurs this season due to their lack of attacking options. Andre Villas-Boas has put his faith in the England international, who has led the line on his own for much of the season.
Victor Moses | Chelsea
Moses boldly declared "there is more to come" after coming off the bench to net a last-gasp winner for Chelsea in their 3-2 victory over Shakhtar Donetsk last week.
The £10million summer signing has been in the shadow of the much-vaunted Juan Mata, Oscar and Eden Hazard since arriving at Stamford Bridge, but continues to impress in his cameo performances.
Theo Walcott | Arsenal
Walcott has been restricted to a fringe role this season, as talks over a new Arsenal contract continue. But, that has not affected his form, with eight goals in all competitions this season.
Edin Dzeko | Manchester City
Dzeko dislikes his new label: "I will never be a super-sub, I want to play."
Javier Hernandez | Manchester United
Ferguson has praised a rejuvenated Hernandez: "He's looking fresh and aggressive with his running, he's always a handful and the way he's started this season I'm certain he'll get to 20-plus goals."