Substitutes are a key part of football, as they help bring a fresh pair of legs on the pitch, and often go on to make an instant impact on the outcome of the game. The Premier League has witnessed quite a few 'super-subs' in its three decades of existence, who have often scored dramatic goals in the final moments of a game.As scoring goals is the most important aspect of the game, most substitutes that come on from the bench are attackers.ON THIS DAY: In 1999, Ole Gunnar Solskjaer became the first player in Premier League history to score four goals as a substitute during Manchester United's 8-1 win at Nottingham Forest. ⁣⁣80' ⚽️⁣88' ⚽️⁣90' ⚽️⁣90' ⚽️⁣⁣History maker. pic.twitter.com/ECRdXEcTWQ— Squawka Football (@Squawka) February 6, 2020Although no player wants to be left on the bench, some are more effective coming on late rather than playing the whole 90 minutes. Let's take a look at the players who've notched up the most goals as substitutes in the history of the English top-flight.10 Top goal-scoring substitutes in Premier League history:#10 Darren Bent - 13 goals 57 appearances, 107.8 mins-per-goal (as a substitute)Darren Bent scored 13 goals as a substitute in the Premier LeagueTraditionally, we may never consider a player who had travelled to nine different clubs in his career a successful one. But Darren Bent might be an exception to that, having scored 106 goals in his Premier League career, though he had more losses with the clubs than wins.He made 57 appearances in the English top-flight as a substitute, scoring 13 times, the same number of goals Andy Cole, Tore Andre-Flo, and Michael Owen scored coming on from the bench. It is his superior ratio of a goal every 107.8 minutes that earned him a place in our list.#9 Edin Dzeko - 13 goals 56 appearances, 89.1 mins-per-goal (as a substitute)Edin Dzeko is a prolific goalscorer for club and country.Manchester City have one of the best strikers in the world in Sergio Aguero in their ranks, but they have struggled to find a reliable backup for the Argentine since the departure of Edin Dzeko in 2015.Dzeko, who now plays for Serie A side AS Roma, had a productive spell with the Cityzens and scored as many as 50 goals in the Premier League. He scored 13 goals as a substitute in 56 appearances, and averaged a goal per appearance from the bench.#8 Victor Anichebe - 14 goals107 appearances, 147.4 mins-per-goal (as a substitute)Victor Anichebe scored most of his Premier League games for EvertonNigerian striker Victor Anichebe made over 200 appearances in the Premier League, mostly with Everton, and more than half were from the bench. As a result, most of the goals that he scored were also as a substitute.Although he only scored 26 goals in the league, 14 of them from the bench, his ratio of 147.4 minutes-per-goal earns him a place on this list.#7 Peter Crouch - 16 goals156 appearances, 178.1 min-per-goalPeter Crouch was the preferred second-choice striker for all of his managersAnother centurion to feature in this list is one of the Premier League's cult heroes, the 6'7'' Peter Crouch. The former England international made a name for himself in the league for his penchant for scoring headers during his time with Southampton, Liverpool, Tottenham Hotspur, and Stoke City.53 – Peter Crouch scored 53 headed goals during his Premier League career, the most of any player. Indeed, he is the only player in the competition’s history to score 50 or more goals with his head. Artistry. pic.twitter.com/2hhoh0DwJN— OptaJoe (@OptaJoe) July 12, 2019Though he made as many as 156 appearances from the bench, his 178.1 min-per-goal ratio is not quite 'super-sub' worthy. Before hanging up his boots, he ended up scoring 108 goals in the league, of which he scored 16 coming off the bench.Also See: 5 Premier League stars and their unique Guinness World Records that you didn't know about