Premier League managers are judged on how many games they can help their side win by coming out on top in a tactical battle against the opposing manager or making a superb substitution at the right time.
A lot has been made of Sir Alex Ferguson's departure from Manchester United as he could change a game before a ball was even kicked.
The legendary Ferguson was the master at playing mind games with players and managers of rival teams.
He would also know when to made a change as seen in the 1998/99 Champions League final when he brought on Teddy Sheringham and Ole Gunnar Solskjaer.
David Moyes has so far not been able to have the same impact on games during his short reign at Old Trafford.
Here we take a look at the amount of goals substitutes for the top seven sides in the Premier League have both scored and created.
Click through the following pages to see the results, which were provided by the Daily Mail.
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