It is widely accepted that a referee and his assistants have one of the hardest jobs in football.
However, history is littered with occasions where the officials have made decisions that have baffled managers, players and supporters alike.
This season has been no different, with a number incidents causing controversy up and down the Premier League.
With that in mind, Sports Mole brings you the top five controversial decisions made by those with the whistles and the flag.
5. Dave Bryan - Not spotting Branislav Ivanovic was offside
Wigan Athletic, who were fighting relegation at the time, were putting up an admirable fight against Chelsea in April. However, all their hard work was undone when Branislav Ivanovic opened the scoring from close range. Having given the incident closer inspection, it would appear that assistant Dave Bryan had failed to spot that the Serbian defender was at least two yards offside when he converted the chance.
4. Martin Atkinson - Failing to send off Mario Balotelli
Quite simply, Balotelli could have ended the career of Arsenal midfielder Alex Song back in April. The Manchester City striker inserted his studs into Song's knee in full view of the watching world. However, Atkinson failed to spot the challenge, with the Italian escaping punishment altogether.
3. Andre Marriner - Allowing Morten Gamst Pedersen to dribble from a corner
Yet another selection for Wigan supporters to bemoan! Back in November Blackburn Rovers scored a goal against them when Junior Hoilett headed in a cross from Pedersen. What referee Marriner failed to spot was that after Yakubu had placed the ball in the corner quadrant, Pedersen simply dribbled the ball out before picking out Hoilett.
2. Martin Atkinson, Bob Pollock - Failing to award Clint Hill's 'ghost goal'
While many will sympathise with the officials over a lack of technology on this one, Hill's headed effort was a good yard over the line before Adam Bogdan cleared the ball out of his net. Pollock, who was running the line, was looking straight at the incident - which makes his failure to spot that the ball had crossed the line even more remarkable. If QPR were to be relegated by one goal this season, Messrs Atkinson and Pollock are likely to be off their Christmas card list.
1. Martin Atkinson - The Chelsea goal that never was
This incident completes a somewhat infamous hat-trick for Atkinson. In what was a crowded penalty area, the referee came to the verdict that Juan Mata's shot had cross Brad Friedel's line during Chelsea's FA Cup semi-final against Tottenham Hotspur. Replays showed that Atkinson had got the decision badly wrong as Chelsea went on to hit Spurs for five.
