A cricket match is presided over by two umpires, whose job it is to make quick decisions on all aspects of the play. They are sometimes jokingly referred to as the men in white (usually umpires wear long white coars), or other less affectionate terms.
Positions
When a ball is being bowled, one umpire (the bowler's end umpire) stands behind the stumps at the non-striker's end (that is, the end from which the ball is being bowled), which gives him a view straight down the pitch. The other (the striker's end umppire) takes the position that he feels gives him the best view of the play. Through long tradition, this is usually square leg - in line with the stumps and a few yards to the batsman's leg side - hence he is sometimes known as the square leg umpire. However, if a fielder takes up position at square leg or somewhere so as to block his view, then the umpire must move somewhere else - typically either a short distance or to point on the opposite side of the batsman.
It is up to the umpires to keep out of the way of both the ball and the players. In particular, if the ball is hit and the players attempt a run, then the umpire behind the stumps will generally retreat to the side, in case the fielding side attempts a run out at that end.
At the end of each over, the two umpires will exchange positions. Because the field switches round between overs, this means they only move a short distance.
Decisions and signals
During play, the umpire behind the stumps makes the decisions, which he mainly indicates using arm movements. Some decisions must be instantaneous, whereas for others he may pause to think or discuss it with the square leg umpire - especially if the latter may have had a better view.
When the ball is in play
These decisions have an important effect on the play and are signalled straight away.
Out
First of all, an umpire will not declare a man out unless asked to, though a batsman may walk if he knows himself to be out; this is nowadays rare, especially in tests and first-class matches. If they think a man is out, the fielding side must appeal, by asking "How's that?" or "How was he?" Appeals are usually shouted loudly enough that the words cannot be made out and may be more similar to a celebration than a question. It has even happened that a player was too busy appealing to stop a ball, and so allowed the batsmen to get extra runs.
The umpire's response, which may take some time, is either to raise his index finger to indicate the man is out, or to shake his head and say "not out".
No-ball
Either umpire may declare a ball to be improperly bowled. In practice, the bowler's end umpire generally calls for the bowler overstepping the line and the other for the bowler's arm not being straight. The signal is to hold one arm out horizontally and shout "no-ball"; the idea being that the batsman is aware of the no-ball's being bowled.
Wide
A wide is declared by sticking both arms out horizontally. Note that if the delivery is a no-ball, it cannot also count as a wide.
Dead ball
If the ball is no-longer considered in play, it is a dead ball. An umpire will only signal this, by crossing and uncrossing his wrists below his waste, if he thinks it is necessary to inform the players (if a boundary is scored or a man is out, which both make the ball dead, the players will obviously already know), particularly if he is interrupting play due to an injury or for any other reason.
Signals to scorers
It is important that the scorers note down the play accurately and therefore the appropriate signals will be made by the umpire when the ball is dead.
Four
If a batsman scores four by hitting the ball across the boundary (not by actually running them), the umpire signals this by waving his arm back and forth in front of him. This signal varies a lot between umpires, from the restrained two short waves, finishing with the arm across the chest, to elaborate signals that resemble a conductor.
Six
A six scored by hitting the ball over the boundary is signalled by the umpire raising both hands above his head, often in a celebratory manner - although he is neutral, a six is considered an achievement.
Bye
If runs are scored from a bye, the umpire will hold up his open palm.
Leg bye
Leg byes are signalled by the umpire touching his raised knee.
Short run
If one of the batsman turned round without touching the popping crease, then a short run is signalled by the umpire tapping his shoulder with his fingers and one of the runs isn't counted.
List of famous umpires
Obviously more to come, and I'm not sure about what to do with the below.
As such it isn't a very popular position and as only the most decisive and knowledgeable umpires are ever entrusted with a test match, it is (statistically speaking) far harder to become a test umpire than a test player, with far less financial reward. The heat and inactivity of the umpires role, combined with the statistical quirks of selection may go some way to explaining some of the unusual quirks of those who perform this vital, yet thankless role.
Common misspelling and questions (FAQ)
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