We’ve all been there.  Your team is a goal down, with 20 minutes to go and you know the only way to get a result is to make substitutions.  But how many?  And who?  Once the changes have been made you can sit back and wait for the sub to score the goal that may salvage a point.  They always do.  Don’t they?

The substitution is the final throw of the dice, and often the sign of a desperate man(ager).  Whilst there are a number of reasons that substitutions may be made (injury, as a result of a red card, to strengthen the defence), the majority are made chasing a goal.  Or two.

I wanted to know how often subs score?  How likely is a substitutes goal to make a difference to the distribution of points at the end of the game?  And which managers are the best at making them?

Therefore the purpose of this post is to evaluate the ‘impact’ of subs, my definition of an impact being when a sub earns a point (or points) for their team and to see what the Premier League table would look like without these impacts.

So far this season (up to 15th April), there have been 1734 substitutions in the Premier League, out of a maximum possible 1938 (89%).  The breakdown is as per the chart below.

Clearly some teams have played more games than others and have therefore had the potential to make more subs, therefore the chart is better viewed as a percentage of potential subs.

As is clear, Mancini prefers to use all of his subs, using all 3 in every game this season apart from the 0-0 draw v Chelsea at Stamford Bridge, whereas Brendan Rodgers has only used 76.77% of his available substitutions so far.  Does this signify a lack of confidence from Rodgers in his substitutes or, alternatively, supreme confidence in his starting 11?

Only once this season has a team made no substitutions in a game, West Brom in their 3-1 defeat to Swansea at the Liberty Stadium.  This is interesting as all 3 of Swansea’s goals were scored within 39 minutes, meaning there was plenty of time left to make changes and possibly benefit from an impact, something that Steve Clarke decided against.

Next we will take a look at the timings of substitutions..

The majority of substitutions are made in the last 15 minutes of games and, surprisingly, only 14% are made in the first 15 minutes of the 2nd half.  This suggests that managers are prepared to wait for 15 minutes to see whether their half-time team talk has had any impact on their teams.  Only when it becomes clear that it hasn’t do they ramp up their substitutions.

Now we know who uses subs and when subs are made we need to look at the number of goals scored by them.

Of 1734 substitutions made, only 87 of them resulted in a goal, or just over 5%.  Obviously some of these substitutions will have been defensive or even goalkeeper substitutes, however I am only interested in goals as a result of subs.

The team having the most success at gaining goals from substitutes is Reading with 10 goals from 84 substitutions (11.90%).  I’m sure we all remember LeFondre coming off the bench 2 weeks running and scoring a brace in both games.  The team with the poorest goals to substitutions is Sunderland with only 1 goal from 88 substitutions (1.14%).  Does that help to explain why Martin O Neill has recently been sacked?

Whilst only 14% of substitutes are made between 46 & 60 minutes, the majority of substitute goals are scored by subs that are introduced in the 46th minute (9), the next optimum time to make a substitution is 68 minutes, with 6 goals coming from subs introduced at that time.

The key time for substitutes to score is within 5 minutes of them being introduced, over 29% of goals are scored in a substitutes first 5 minutes on the pitch.

As mentioned earlier however, there is a difference between a sub scoring a goal and the goal making a difference to the final distribution of points.  For example, Chelsea subs have scored 5 goals this season, yet none of these goals have made any difference to the number of points they have received, i.e. zero impacts.

Reading continue to top the table, with 7 impacts from their 10 goals and Man City second with 6 impacts from 9 goals.  Chelsea, Wigan, Southampton, West Brom & Sunderland have had no points changing impacts from substitutes so far this season.

Converting the impacts into overall points won at the end of the games then gives us a definitive view of who is benefiting the most from the use of substitutes.

With 15 points gained as a result of substitutes impacts, Man City are gaining the most from their use of substitutes.  I would suggest this isn’t much of a surprise as they generally have a very strong subs bench to choose from, however, so have Chelsea and they aren’t benefiting from it all.

Interestingly, 4 out of the top 5 teams in the impact table (with the exception of Reading) are in the top 5 for total substitutes used.  Therefore, my advice for the use of substitutions would be as follows:

• Use all of your substitutes, every game
• Make your first sub in the 46th minute
• If they haven’t scored within 5 minutes of coming on, replace them.  In the 68th minute.

The last thing to do is look at the Premier League table with the points resulting from substitutes impacts removed.

The biggest losers without substitutes impacts would be Man City, dropping a massive 4 places down the table and whilst both Villa & Everton would climb 3 places apiece, Wigan would also breathe a sigh of relief climbing out of the bottom 3.

Managers will always call on substitutes to change games, even though only 5% score and only 2% have an impact on the final distribution of points.  Who’d be a manager eh?!