Howard Webb reminding you to keep your hands and arms
inside the VAR at all times.

Somewhere around minute 10 of MLS’s series of videos on the use of the video assistant referee (or VAR), once the novelty of Howard Webb’s accent and the EPCOT Center ride background music wore off, I figured I’d spare casual fans from having to sort through the vagaries of VAR, which arrives in full force this weekend. The Union’s game with FC Dallas Saturday night is one of the first in the league (and the world) in which the system will be utilized, which may lead to some kinks worked out on the fly. Plenty has been written on the subject, but here are the nuts and bolts.

I should say that MLS’s videos make things pretty easy to understand and Webb has become an important spokesperson for implementing this system, so if you have time to, by all means enjoy. But if you don’t – or you just want to preserve the pristine mental image of a beardless Webb – then allow me to distill the main points.

Two phrases are key. “Attacking phase of play” (APP) is the contiguous possession of the ball by a team that leads to a reviewable instance, which I’ll list shortly. Any of the numerated mistakes that occur during the APP are up for review, either to the benefit or detriment of the offending team.

Another is “clear and obvious mistake.” Video reviews are initiated by the VAR, who is constantly monitoring game actions on the sidelines and can signal to the head referee the suspicion of a “clear and obvious mistake.” The head referee can then decide to take a further look and makes the decision of whether there is conclusive video evidence to change the call.

Four categories of "match-changing" events can be reviewed: Goals, penalty kicks, red cards and mistaken identity. We’ll take them one by one.

- Goals. The most simple goal review is if a ball fully crosses the line. But there’s much more to review, which is where the APP comes into play. The VAR can recommend for review the following events in the APP: handball by the attacking team, offside by the attacking team, foul by the attacking team or whether the ball goes out of play.

- Penalty kicks. This applies to PKs awarded and not awarded. In addition to the basic review of the actual infraction or non-infraction in the box, the VAR can recommend for review other elements of the APP, including handball by the attacking team, offside by the attacking team, foul by the attacking team or whether the ball goes out of play.

- Red cards. Review is applicable only to straight red cards or infractions where a foul or yellow card is awarded but the VAR believes it’s possible a “clear and obvious” red is missed. (Here’s where things can get squirrely.) VAR can, then, recommend a yellow be reviewed to determine if it should’ve been a red, but can’t recommend a yellow, even a second yellow, be reviewed to determine if it wasn’t a yellow. (In this instance, the “clear and obvious mistake” mantra is vital to differentiate the VAR’s conception of a red vs. the head referee’s so as not to bring two judgement calls into conflict.) In this instance, the APP applies to the passage of play before the red card occurs to see if an infraction by the attacking team was missed that would’ve terminated play prior to the red. This is particularly prevalent in the red for the denial of a goal-scoring opportunity, or DOGSO.

- Mistaken identity. This one is self-explanatory and, thankfully, rare. This is applicable for all applications of "disciplinary action," i.e. reds and yellows.