This.
Still it's a shame that it was Liverpool benefitted from it.
But a match lasts till the end, no matter how much extra time is given and no matter how much the referee decides to add to that.
Personally there is a flaw in that rule. Let's take a club who leads 1-0 until the 80th minute. They have scored their goal in the 15th minute and from them on they start to waste time.
In the 80th and the 84th minute their opponents score goals, so in the 85th minute they are loosing 1-2 and then the refs gives 6 extra minutes (3 minutes for substitutions and 3 mùinutes for wasted time by the team that is now 2-1 down). I don't blame the ref, but at that moment the time that is wasted by the loosing team should not be counting.
My reasoning:
The club that at the time led 1-0, has stolen this time from the club that was being led. They stole time in order that the other club could not come back.
Once the club has come back and is winning, this is totally irrelevant. Now the team that has stolen time is being led, but since it was that team in the first place that wasted time, refs should add this time.
There is something fundamentally unfair in all this.
But for the record: i don't agree with Mehtab (i rarely do).