You just know a trolling is going to occur when:

Opponent is 30-40% weaker.
Opponent is in the bottom 2 or 3 of the League.
Opponent Manager doesn't watch the game.
Opponent scores in first 5 minutes or with first attack.
Your best player is injured in first 5 minutes.
You have a key player sent off with a straight Red.
Your opponent has a player sent off then suddenly scores twice in 5 minutes.
You batter the opponent but his GK is Neuer/Buffon/De Gea/even Gordon Banks rolled into one.
Your best AML/AMC/AMR cannot score in a brothel.
You have 10+ shots on target and score maybe 1, opponent has 3 shots on target and scores 2.
Desperate tactical changes/subs make no difference to the outcome.
You give up at 70 minutes knowing there's SFA you can do so just roll with it.

I am sure we have all seen this.