Boyce: Referees not told to be lenient
With two matches remaining, the 2014 finals in Brazil have seen 10 dismissals - the lowest figure at the tournament since 1986, when 52 games were played, 12 less than in the competition's current format.
Spanish official Carlos Velasco Carballo came under criticism for failing to brand a caution until the 64th minute of Brazil's feisty quarter-final clash with Colombia, leading to speculation that referees had been asked to keep their cards in their pocket by FIFA.
Boyce rejected such claims, though, and was fulsome in his praise of the officiating seen at the finals thus far.
"I think the refereeing has been superb, and it has not happened by chance," he said.
"I have seen all the courses and seminars, listened to the instructors, and spoken to the referees and they have told me they have never had such good preparation for a World Cup.
"The referees have been told to only send a player off if they were 100 per cent certain it was a red card, but nothing has ever been said about being lenient."
Boyce also believes the tournament as a whole has been a success, after previous concerns surrounding security and the readiness of the stadia.
"We have seen some tremendous matches," he added.
"There were a lot of worries before the tournament, security was a big concern, stadiums were a big concern, but in fairness it has gone a lot better than people expected.
"Brazil deserves an awful lot of credit because there was a lot of speculation there would be big problems."