Polos governing body has found two players guilty of misconduct during a match at the Beaufort Polo Club, Gloucestershire, last month.
Argentine veteran Ernesto Trotz pleaded not guilty to striking another player, Anthony Sharp, with his mallet during the subsidiary final of the Arthur Lucas Cup. Trotz, now seven goals, used to hold a10-goal rating and has played in England throughout his career.
The Hurlingham Polo Association (HPA) fined Trotz £5,000 and imposed a weeks ban on his playing in any match or practice chukka at an HPA club, so he missed his first Gold Cup league match.
Trotz was last disciplined by the HPA in 1992. Then, he was fined £5,000 for striking fellow Argentine professional Gonzalo Pieres in a Gold Cup match at Stedham, West Sussex.
In the same subsidiary final at the Beaufort last month, Argentine umpire Andrea Vianini was found guilty of taking a bottle of beer on to the field in his ball bag and throwing the empty bottle into the safety zone. The match was stopped so that the bottle could be removed.
A statement by Mark Vestey, chairman of the disciplinary board, said: Such a case of misconduct would not normally be a matter for the stewards,it was referred only because it occurred during the same match [as Ernesto Trotzs incident] and involved the same witnesses. We took into account the fact that Andrea Vianini apologised and agreed that it was unacceptable to take beer on to the field or drop a bottle in the safety zone, and decided to censure him for his unprofessional behaviour.
Vianini who was fined £2,000 in 1998 for playing under the influence of illegal drugs and Trotz must share the costs of the hearing.
The HPA does not perform routine tests for alcohol, but the limit is set at the same level as in racing, at roughly half the driving limit, and until this season, drug testing was done piecemeal.
But the HPA has now embarked on an organised programme of drug testing for substances such as cannabis, cocaine and opiates. It has taken saliva samples from players at Guards, Cowdray, Berkshire, Beaufort and Coworth. From the 102 tests taken so far, none has been positive.