Substitutions in football are often born out of necessity.
Earlier, injured players would leave their teams with fewer men on the pitch. However, a law was implemented later on regarding substitutes.
With time, football managers saw the tactical benefits of being able to switch their players around, and the super-sub term was born.
On that note, here are the seven players who came on a substitute to change the course of a football game:
1. Ole Gunnar Solskjaer (Manchester United, 1999 Champions League final)
Ole Gunnar Solkjaer signed for Manchester United in 1996.
The Norwegian debuted coming off the bench to score his first goal for the Red Devils. Solkjaer would go on to score a total of 29 goals as a substitute, but none more important than his winner in the 1999 Champions League final against Bayern Munich.
What's more incredible is that the equaliser in that game came from another substitute, Teddy Sherringham, in injury time before Solkjaer's winner completed an incredible turnaround at the Camp Nou in Barcelona.
2. Gareth Bale (Real Madrid, 2018 Champions League final)
Gareth Bale was fuming after starting the 2018 Champions League final against Liverpool on the bench.
The Welshman entered the pitch in the 61st minute, with the match tied at 1-1. Only three minutes after coming on, Bale scored a magnificent bicycle kick goal.
A brace from Bale courtesy a Loris Karius error ensured Los Blancos' record-extending 13th Champions League/European Cup triumph.
3. Juliano Belletti (Barcelona, 2006 Champions League final)
With the 2006 final Champions League final against Arsenal hanging in the balance at 1-1, Barcelona were desperately craving for a goal that would give them their fourth title in the competition.
Fortunately for them, an unlikely hero emerged in the 81st minute, who scored the match-winning goal. He was none other than Juliano Belletti who came on in the 71st minute for Oleguer Presas.
Following Samuel Eto'o's equaliser, itt was a goal that broke ten-man Arsenal's hearts in Paris as Barça's win kickstarted their domination on the European stage.
4. Georginio Wijnaldum (Liverpool, 2018-19 Champions League semifinal second leg)
In the Champions League semifinal second leg against Barcelone, Jurgen Klopp got his puzzle pieces right before Trent Alexander-Arnold, and Divock Origi combined for the famous corner.
Georginio Wijnaldum came on for Andrew Robertson at half-time and scored twice in just over two minutes. Barcelona were beginning to get the Rome flashbacks sending them into despair as the Reds reduced a three-goal aggregate deficit to just one.
Liverpool would then go on to complete one of the greatest Champions League comebacks of all-time, winning 4-0 on the night and 4-3 on aggregate to advance to consecutive finals in the competition in as many years.
5. Eder (Portugal, 2016 European Championship Final)
Super substitutes are not just limited to the Champions League.
Portugal faced the seemingly impossible task of winning the Euro 2016 final at the expense of hosts France in Paris. They did have their captain Cristiano Ronaldo, who tearfully hobbled off the field after only 25 minutes, having picked up an injury.
That's when Eder went from a local nobody to a hero, scoring the final's only goal in the 109th minute as Portugal became the newest European champions in Saint-Denis.
6. Mario Gotze (Germany, 2014 FIFA World Cup Final)
What's bigger than winning a FIFA World Cup? Winning a World Cup and scoring the decisive goal in the final!
We're sure Mario Gotze dreamt of this moment but he never thought it would come true. When he was taking his first steps in football, German legend Franz Beckenbauer described him as the 'German Messi'.
With the goalless final of the 2014 FIFA World Cup against Argentina heading to extra time, Mario Gotze came on in the 88th minute in place of the competition's all-time top-scorer Miroslav Klose.
Seven minutes from a penalty shoot-out, with the final yet to witness a goal, Gotze controlled an Andre Schuerle cross on his chest before volleying the ball into the net. In the process, the diminutive German became the first substitute to score a goal in a World Cup final, and the youngest player to score in the final of the quadrennial tournament since fellow 22-year-old compatriot, Wolfgang Weber.
Though his career has taken a sour turn since then, we imagine Gotze wouldn't change a single moment of it.
7. Robert Lewandowski (Bayern Munich, 2015-16 Bundesliga)
In a 2015-16 German Bundesliga game, Bayern Munich were down 1-0 against Wolfsburg when Pep Guardiola subbed in Robert Lewandowski for the second half.
Lewa scored a goal in the 51st minute, doubled his team's lead in the 52nd, and completed his hat-trick by the 55th. He made it four two minutes later, and five at the hour mark.
It took Lewandowski 9 minutes to score five goals, that's a goal every 1.8 minutes. The final score was Lewandowski 5-1 Wolfsburg. It is the fastest hat-trick, quadruple, and five-goal haul in Bundesliga history.