(CNN) -- Who'd be a referee? When the crowd aren't getting on your back you've got the players acting up or giving you an earful.

So if someone described your refereeing as "the best," you could be forgiven for feeling a small surge of pride. But when the person praising you has been called the world's most notorious match fixer, then it's time to show yourself a red card.

Wilson Raj Perumal says he corrupted many football players and officials during a long criminal career, but there is one person who stands out from the crowd. His name was Ibrahim Chaibou, a referee from Niger.

"He was the best, he was the best, but not from FIFA's point of view," Perumal told CNN during a wide-ranging television interview about his match-fixing days.

Perfect partner

The Singaporean, who is now helping European police with match-fixing investigations, claims to have rigged the results of up to 100 matches over a 20-year period, boasting of a 70-80% success rate.

Chaibou, who he describes as "very bold," became one of his favourite match officials.

According to Perumal, the referee's first match fix was an international friendly between South Africa and Guatemala in May 2010 -- one of several warm-up matches played ahead of the 2010 World Cup which the Rainbow Nation hosted.

Watching highlights of the game on YouTube, Perumal gives a running commentary on the major incidents.

"It's crazy," Perumal says as Chaibou awards South Africa a penalty kick. The quality of the footage is poor, but the fixer knows what happened.

Answer this series of questions:

1. Who corrupted many football players?
2. How many people stand out to him?
3. Who is that?
4. Does he tell CNN a review?
5. What does he tell them?
6. What does he help European officers do?
7. What is the percentage boast?
8. Where does he look at highlights?
9. What does he give on there?
10. Who does he award?
11. For what?
1. Wilson Raj Perumal
2. one
3. Ibrahim Chaibou
4. Yes, Perumal told CNN
5. Perumal told CNN, "he was the best, but not from FIFA's point of view"
6. he helps with match-fixing investigations
7. He boasts a 70-80% success rate
8. He watches on YouTube
9. He gives running commentary on the major incidents
10. South Africa
11. a penalty kick