17

You are right that the French Open is the only Grand Slam tournament without Hawkeye, The reason is that Clay, unlike grass and hardcourts, leaves a mark that players and umpires can check and verify if the ball was in or out. You can argue that some mistakes can be made but that's quite rare, A hawkeye system is very expensive and the cost/benefit ratio ...


10

This can be answered definitively, without much speculation, by reading articles from the NFL. The initial replay system, in place from 1986 to 1991, was scrapped for two reasons: After a six-season run, instant replay met its demise in 1991 when 17 owners voted against renewing the system. The belief: The system delayed games too much and failed to get ...


8

A coaches' challenge is not permitted on scoring plays. Initiating a challenge when one is not permitted to do so is a foul. On a scoring play, the replay official may initiate a review except when the team that the referees ruled against commits a foul that delays the next snap. The illegal challenge by the coach was such a foul. Therefore, the disputed ...


8

Actually FIFA has changed some of the rules. Not really an instant replay, but still huge progress. The German company Goal Control has been handed the contract by FIFA to provide goal line technology at the World Cup in Brazil. There will be 14 cameras – seven for each goal mouth – mounted at or near the roof of the stadium, capturing images at ...


8

As of 2014, Major League Baseball adopted its current replay system, in which each manager can challenge a call one time per game, and gets a second one if the first call that they challenged is overturned. The official rules for challenges can be found at http://m.mlb.com/official_rules/replay_review.


7

No. Once one team challenges the play, that challenge covers all reviewable aspects of the play, at least as of the most recent rules (2015). From Rule 15, Section 2, Article 3: Note 2: All reviewable aspects of the play may be examined and are subject to reversal, even if not identified in a coach’s challenge or if not the specific reason for a Replay ...


7

There is NO good reason for the failure to implement video plays in professional soccer. Far from "breaking the flow of the game" it would actually prevent all those ridiculous delays where the players protest the referees decision. When a video replay will reveal the truth there will be no point in arguing, just as there will be no-point pretending that ...


7

There are no challenges in the NHL. All replays are automatic: goals are reviewed by the video judge, with help from the war room in Toronto. Coaches do not have the ability to initiate replays in any form. Penalties are never reviewable, unless the timing relates to a goal. All goals are reviewed (at least cursorily) by the Video Goal Judge, and further ...


6

Bottom line: because that's what rules say. Quoting from the 2015 Rulebook, Rule 15, Section 2, Article 1: Each challenge will require the use of a team timeout. If a challenge is upheld, the timeout will be restored. As for why that was the rule chosen by the NFL, you're into the area of speculation, but a challenge is in some ways similar to a timeout ...


6

The National Hockey League also has a coach's challenge, as of the 2015-2016 season (official announcement). Coaches have a single challenge, which can be used to review a scoring play. If the challenge is unsuccessful, the team loses its timeout. If successful, they retain their ability to challenge later.


6

He leaves the goal line right when the shot is taken. This is quite normal behavior and accepted by the referees. It is very hard to see and the referee also has to watch the other players when they try to go after the ball too early, which makes it even harder. While he's not standing exactly on the line (which is tolerated to some extent.. the referees ...


6

There are likely two possible reasons this technical breach of the Laws was not penalised. The offence was so minor that the referee was unable to detect it. The referee applied his discretion under Law 5, Section 2, Paragraph 1, deciding that it would be inappropriate to penalise such a minor offence with a caution and retake. Law 5, Section 2, Paragraph ...


5

Absolutely, I've seen that exact scenario happen many times. It usually results in the other player having to request the challenge since the call gets changed/overruled. Challenges are available for any call, whether it's a linesperson making the call or a chair umpire. See VII. The Competition PDF here. Look at page 130 - Section VII, #7 where it says ...


5

It's not a coach's challenge per se, but cricket has the concept of player reviews, where either the batsman or the captain of the fielding side can request a review of an umpires decision.


5

The replay official is supposed to let the ruling on the field stand unless there is "indisputable video evidence" that the wrong call was made. From the NCAA Football 2013 and 2014 Rules and Interpretations, Rule 12 (Instant Replay), Section 1, Article 2 (Philosophy): The instant replay process operates under the fundamental assumption that the ruling ...


5

If the goal was scored by the team who should be awarded a penalty, the goal should be awarded. This is standard officiating practice in the case of an advantage to the attacking team. If the goal was scored by the team who committed the foul and should concede the penalty, the section of play is likely to be ignored and the penalty given, as this would be ...


5

Nij's answer sums up the general principles and the correct outcome. I will attempt to answers based strictly on the Laws. Law 10 - Determining the Outcome of a Match, Section 1 - Goal Scored: A goal is scored when the whole of the ball passes over the goal line, between the goalposts and under the crossbar, provided that no offence has been committed by ...


4

Houston RB Justin Forsett touched the field (knee and elbow) and should have been called down. The play would have been reviewed, as are all scoring plays, and the ruling on the field would have been overturned. Because Schwartz threw the challenge flag on a play he couldn't challenge by rule, the play could no longer be reviewed. Instead, The ruling on the ...


4

I strongly suspect that the manufacturers of Hawkeye and similar ball tracking systems would actually prefer not to have a hard 'ground truth' to compare to being beamed live to millions of viewers. These systems are not as accurate as the TV graphics imply and there use as part of the umpiring process is not all to do with accuracy. It is as much about ...


4

Here's a link to an article regarding it's first use in competitive play. The official procedure right now appears to be: The VAR (video assistant referee) automatically reviews every goal, every red card and all penalties, and communicates directly with the head referee, who ultimately decides whether to resort to the monitor. It appears that behind ...


4

Jim Schwartz's attempted challenge against the Texans in 2012 probably counts here. What happened: Texans running back Justin Forsett was knocked down, but got up and continued to run. The play was called a touchdown. As this was a scoring play, it was subject to automatic review. Jim Schwartz threw his challenge flag. Because the play was already subject ...


4

Referees refer to the same Laws of the Game no matter whether they trust VAR or their own eyes when they make decisions. The referee called penalty because he reviewed VAR footage and decided that it was a deliberate handball. Law 12 – Fouls and Misconduct - Handling the ball states: Handling the ball involves a deliberate act of a player making contact ...


4

This question is based on two false premises: that an unintentional handball is a foul; and that the referee, Pitana, came to the conclusion that Perisic's handling was unintentional, yet still awarded a penalty kick. Most free-kick offences in Law 12 (i.e. fouls) do not require intent. The majority simply require carelessness, recklessness or excessive ...


3

At present the problem with not allowing Hawkeye to automatically correct a wrong call is the cost of installation. Many articles suggest the cost is $60,000-$100,000 per court. The price will go down as the technology improves but it is too high to be installed at every place as of now. Another thing associated with cost is the likelihood of technical ...


3

In Field Hockey each team has one video umpire referral per match, it seems limited to FIH World-Level competitions though (/when facilities are in place). As with the cricket example, it is the captain doing the actual challenge. If the challenge is succesful they keep the ability to challenge, if not they can no longer challenge in that game. As long as ...


3

For FIVB-conformant matches: The team has to specify the error to verify. If the error has not occured the team loses the challenge. This is also the case if another arbitrary error occurs, i.e., only the error specified by the team is checked. This has already lead to such funny situations as you described. There is a list of verifiable errors here, ...


3

Clay courts leave a visible mark which shows where the ball lands. This is the reason why the staff at Roland Garros clear the court often during a match so there wont be overlap of marks(or mistake of the actual mark), which can cause confusion. If a ball is questionable, then the referee will come down and check the mark on the court and make his ...


3

The video assistant referee team (VART) constantly checks all play for any of the four situations, and searches for clear and obvious errors in such a case. Each member of the VART has a particular role. The VAR leads the VART and is in communication with the referee at all times and performs the main review of each incident, via two screens showing five ...


3

A challenge with no timeouts left is not possible. And it will cost the team 15 yards, if the coach tries to do so. Section 2 - Instant Replay A team may not challenge a reviewable play: after the two-minute warning of each half; throughout any overtime period; after committing a foul that delays the next snap; and after exhausting all of ...


3

Law 5.4 states that the VAR uses replay(s), so there is no limitation in what sort of replays are being used. Usually all with a proper perspective on the scene. The assistance from the video assistant referee (VAR) will relate to using replay(s) of the incident. When you watch the live footage of the VAR or referee in the review area you can clearly ...


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