Don't judge a substitution's success by the scorer alone

What does the coach want to change?

When you see a substitution, the first question should not be only who came on. Look at whether the team needs a goal, wants to hold a lead, or is having problems on one flank. If the coach has not explained the reasoning, label your interpretation as tactical analysis rather than presenting it as knowledge of the coach's intentions.

The new player might take the same position as the one replaced or take on a new role. There can be changes like a winger coming on and pulling another player into midfield. Therefore, don't conclude that the system is unchanged just because the position name on the team sheet is the same.

Look fairly at before and after coming on

After the substitute comes on, if attempts increase, don't immediately assume it's because of him alone. At the same time, the opponent may also substitute, drop back, or receive a red card. Since many match situations are changing, you need to distinguish between correlation and causation.

Judging a substitute after limited playing time solely by pass completion percentage or per-90 stats can be misleading. A single event can greatly change his numbers, and off-ball duties may not show in stats. State the playing time and focus on how the team played after he came on.

A substitute can be effective without scoring

A substitute can pull an opposing defender outside to open central space for a teammate. He can press from the front and force the opponent to lose the ball quickly. For a team holding a lead, keeping the ball and taking it to safe areas can also be valuable work.

On the other hand, don't automatically label a scorer as someone who did everything well. You can separately note any other moments when he failed to fulfil his role, where the evidence supports that assessment. A quality assessment is acknowledging the match-changing finish while fairly viewing the whole performance.

Being on the bench and actually playing

Being named on the bench does not mean he entered the match. Check who came on, who went off, and the time with a substitution event list. Because data can be adjusted after the match, do not replace missing playing-time data with an assumed zero. Don't confirm an injury substitution without official announcement.

UEFA's technical reports on substitutions guide looking at the substitute's role in relation to team tactics. In the article, explain in order the original problem, how the role changed after the substitution, and the visible result. That way, you can answer the question of whether the substitution was good more completely than with just one goal.

Putting it into practice

For a practical note, try writing in one sentence the team's problem before the substitution. Then watch in the following minutes how the incoming player tries to solve that problem. Note both successful and unsuccessful actions. Recording the problem before the substitution and following what happens afterwards can reduce the temptation to invent explanations once the final result is known. It also helps distinguish the coach's decision from the player's execution.