Chelsea midfielder Eden Hazard has apologised after he was sent off for kicking a ball boy in a League Cup game at Swansea City on Wednesday.
We take look at some other sporting controversies featuring the boys - and girls - employed to help keep the action going:
OVER-EAGER BALL BOY STOPS PLAY:
An inattentive ball boy sparked confusion during a match between Andy Murray and Victor Troicki at the 2011 French Open by running onto the court mid-point. As Troicki lined up a smash, the boy dashed onto the court in the mistaken belief the ball had gone out, before retreating sheepishly to his position by the umpire's chair. The umpire ordered the point, which Troicki won, to be replayed, and Murray went on to win the match.
CABAYE LOSES PATIENCE AT GOODISON PARK:
Newcastle United midfielder Yohan Cabaye, a team-mate of Hazard's at Lille, got involved in an altercation with a ball boy in a match at Everton last season. With Newcastle trailing, Cabaye was seen to angrily wrench the ball from the hands of a pitch-side ball boy. The incident sparked jeers from the home fans, but Cabaye sought the boy out at half-time to apologise.
BRAZILIAN BALL BOY SCORES GOAL:
A Brazilian referee was left red-faced after allowing a goal scored by a ball boy to stand in a regional tournament in Sao Paulo in September 2006. Standing behind one of the goals, the boy fielded the ball after a wayward shot and then casually kicked it into the goal when the referee's back was turned. The referee, Silvia Regina de Oliveira, said she had awarded the goal on the advice of one of her assistants.
HENMAN TAKES ANGER OUT ON BALL GIRL:
Before Tim Henman had won the hearts of British tennis fans with his string of near-misses at Wimbledon, he landed himself in hot water in 1995 for angrily hitting a ball at a ball girl during a doubles match. The ball struck the girl on the face and Henman was disqualified from the tournament along with his partner, Jeremy Bates. He later apologised and planted a kiss on the girl's cheek that one tabloid newspaper dubbed: 'the Hen-peck'.
BALL BOY LOSES BEARINGS:
A ball boy displayed too much eagerness to retrieve the ball during a league match between Tottenham Hotspur and Bolton Wanderers in May 2010 when he ran on the pitch to collect it before it had even gone out of play. Bolton left-back Paul Robinson looked incredulous when the boy stopped the ball as he moved in to play it, and play was restarted with a drop-ball.