London derbies don't come much bigger than Chelsea and Tottenham battling for the Champions League.With no fit available strikers Jose Mourinho opted for an extremely defensive line-up, ready to park the bus after throwing Dele Alli under it - the playmaker was dropped, perhaps a result of his outburst in midweek against RB Leipzig.It was clear from the off that Mourinho planned to sit deep and hit his old club on the break.That lasted just 15 minutes, however, until Olivier Giroud broke away from Toby Alderweireld, was initially denied by Hugo Lloris.Ross Barkley then hit the woodwork before Giroud nestled in the rebound on his first start since November.

Marcos Alonso then doubled the hosts' lead with a sweetly hit strike from just outside the box early in the second half.

Things could have got a lot worse for Tottenham as Giovani Lo Celso nearly got himself sent off for a bad challenge on Cesar Azpilicueta. 

The Argentine's studs made contact with the defender's shin while he was down on the turf. 

Somehow, VAR decided to let him off despite the tackle looking worse with every replay. 

Bizarrely, however, Stockley Park then told BT Sport that they had committed a human error and that it WAS a red card. 

Presenter Jake Humphrey tweeted: 

"BREAKING: We have been speaking to Stockley Park who have admitted they got the decision wrong and Lo Celso should have been sent off.."

What?! On the one hand, Stockley Park deserve credit for holding their hands up, but it just goes to show another fault with the system. 

Their retraction took place so long afterwards that there was absolutely nothing that could be done. 

It's a good job the decision didn't affect the result or serious questions would be asked.

Antonio Rudiger's late own goal threatened a nervy finish but for once, Chelsea held on. 

Another nightmare afternoon for VAR.