The Video Assistant Referee was used for a second time in English football in Wednesday night's Carabao Cup semi-final first leg between Chelsea and Arsenal.
VAR can be used in decisions relating to the awarding of goals, penalty kicks, the issuing of straight red cards and cases of mistaken identity.
Here, Press Association Sport looks at when the technology was consulted at Stamford Bridge.
- 29 mins - Referee Martin Atkinson appeared to consulted the VAR after Calum Chambers and Cesar Azpilicueta jostled for position ahead of a corner. Chambers appeared to shove the Chelsea defender, who performed a backwards roll and appealed. It appeared Atkinson consulted VAR Neil Swarbrick before calling both players over and issuing a ticking-off.
- 39 mins - Atkinson appeared to speak into his headset to consult the VAR again after Ainsley Maitland-Niles hurdled Victor Moses in the Chelsea penalty area. Replays showed no contact, so no spot-kick, and that the Arsenal man was taking evasive action, rather than trying to deceive the official.
- 88 mins - Atkinson consulted Swarbrick after 88 minutes ahead of a Chelsea corner, after Danny Welbeck had beaten Cesc Fabregas to the ball, with the latter going down in the box. No penalty.
