Why Tottenham's winner against Sporting CP was ruled offside

Tottenham Hotspur were denied a 95th-minute winner against Sporting CP in the Champions League following a three-minute VAR check.

A victory would have sent Spurs into the knockout stages as group winners, but after drawing 1-1, they need another point against Marseille to secure progression next week, while a win would seal top spot for good.

Antonio Conte's men, who had responded well after falling behind in a lacklustre first half, were incensed that Harry Kane's goal was not allowed to stand, and the Italian was harshly sent off for his touchline protests.

But was the VAR right to take so long with their decision? Was the call even the correct one? Are Tottenham right to feel aggrieved? We have some answers...

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What is the offside rule?

Yeah, you know a decision is a close one when this is whipped out.

For a fuller explanation of the law, you can read here, but we will only focus on some of the parts relevant to this case.

A player is in an offside position if:

• any part of the head, body or feet is in the opponents’ half (excluding the halfway line) and
  
• any part of the head, body or feet is nearer to the opponents’ goal line than both the ball and the second-last opponent, including the goalkeeper

The hands and arms of the attacking player are not considered in offside decisions as you cannot score a legal with these body parts.

A player who is level with the second-last opponent is not in an offside position.

An offside offence has also been committed if a player is:

• gaining an advantage by playing the ball or interfering with an opponent when it has rebounded or been deflected off the goalpost, crossbar or an opponent OR been deliberately saved by any opponent

The guidelines for a "deliberate play" are defined as:

• The ball travelled from distance and the player had a clear view of it
• The ball was not moving quickly
• The direction of the ball was not unexpected
• The player had time to coordinate their body movement, i.e. it was not a case of instinctive stretching or jumping, or a movement that achieved limited contact/control
• A ball moving on the ground is easier to play than a ball in the air

Was Harry Kane offside against Sporting CP?

Let's quickly run back through the move.

Ivan Perisic's initial cross from the left towards the back post came with Kane and Emerson Royal standing in onside positions. That part is fine.

The Brazilian's header back across goal is deflected on by Flavio Nazinho before being flicked up and in by Kane.

However, from most camera angles, Kane is fractionally standing ahead of the ball and the last defender when Emerson heads it, meaning that he is legally, if cruelly, standing in an offside position.

As the deflection off of Nazinho is not a deliberate play (as defined above), Kane's position is not reset. This rule allowed Kane to win a penalty against Liverpool at Anfield in a 2-2 draw back in 2018, as Dejan Lovren's flick was a deliberate act which allowed the otherwise offside Kane to return to legal play before being fouled.

Eric Dier and BT Sport pundits insisted that because Emerson's header went backwards before hitting Nazinho, the goal should have stood. However, the direction of the ball is irrelevant as Kane is still standing ahead of the last man when it is last touched by a teammate.

Semi-automated offsides are in use during the Champions League group stage and would likely have told the officials that Kane was ahead of the ball, with the three-minute check perhaps taking place over whether Nazinho's deflection was a deliberate act, eventually deducing that it was not.

Spurs fans' main gripe now is whether or not Kane was indeed ahead of the ball when it was played, with some camera angles suggesting so more than others.

Sporting would have had little complaints about a no-call if VAR was not in use, but judging by the final frame shown by broadcasters, Kane was offside and the decision was correct.