There was no Video Assistant Referee (VAR) in the Champions League group stage, but the replay system was introduced just last month in the round of 16. It's been getting plenty of use ever since. But at no point has it been more critical in the competition than on Wednesday in the crazy Manchester City vs. Tottenham game. 

It was a seven-goal thriller where Spurs were the beneficiary of two huge reviews. The goal that saw Tottenham through was reviewed for a handball but it was overturned, and then a late goal from Manchester City was reviewed for offside, and it was ruled no goal. 

Here's a closer look at the decisions and what a World Cup final referee told CBS Sports about them.

It was 4-2 Manchester City, and Tottenham needed one more goal to take the lead on away goals. Fernando Llorente put the ball away 73 minutes in on a corner, but the ball looked to come close to hitting his hand. Or was it his thigh? Here's the video of the goal:

Now, it kind of looks like the ball may have touched near his elbow, which would be a handball. But it didn't seem clear. Take a look at this image:

So was it the right call? A World Cup final referee told me after the match that it was the correct call due to inconclusive evidence:

"From what the Turkish referee saw on the screen, the images can give the impression that the ball hits his arm, but nothing is certain. The replays that they showed, it doesn't clearly show it. Yes on the thigh. It could have grazed his arm. The suspicion of a handball isn't what counts. You have to be sure."

So that goal gave Spurs the lead. Manchester City needed one more goal, and they found the back of the net in added time. Raheem Sterling looked to have secured his hat trick and City's spot in the semifinals, but when Sergio Aguero received the ball at the beginning of the play, he was offside when the ball touched Bernardo Silva. Take a look:

For the ref, it was an easy call. 

"Yes, Aguero was offside. There is the pass back, it hits his teammate and from there, it's like a pass with him offside."

You can watch the Champions League semifinals, which are sure to include more controversial calls, on fuboTV (Try for free).

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