FIFA president Gianni Infantino says Barcelona's remarkable comeback victory over Paris Saint-Germain showed football's law makers should be careful with adjusting the rules.
Infantino added that video assistant referees (VARs) will ensure "clear mistakes" will be corrected, although he refused to comment on the controversial penalty award for a foul on Luis Suarez that resulted in Barca's fifth goal.
VARs are being introduced gradually on a trial basis and replays showed contact between Suarez and Marquinhos was minimal.
Trailing 5-3 on aggregate after a 4-0 first-leg loss, Barca needed three goals with two minutes of normal time remaining and prevailed 6-5 courtesy of Sergi Roberto's strike in the fifth minute of stoppage time.
Infantino said in London on Thursday: "Whether that particular case was an injustice or not, we can leave it to the judgement of the referee [Germany's Deniz Aytekin].
"What we saw was an incredible football match, whatever the result would have been at the end. This shows that football is really a fantastic game.
"Whenever you have the feeling you have seen everything, something else comes along that you've never seen before. It's just amazing and incredible.
"We have to really be careful in the IFAB [International Football Association Board] if we want to touch the rules, because football is such an incredible game.
"In this case, I don't know if it was a clear mistake or not but, in future, when there are clear mistakes, this will be corrected by the video assistant referee so we can make sure decisive matches are not decided by mistakes made in good faith by the referee."
The IFAB is to discuss a range of subjects this month, a law change that would allow only captains to speak to referees, sin bins, video replays, extra substitutions and a change to penalty shootouts based on the format used for tiebreakers in tennis.