What are the reasons why Sun Bin can help Tian Ji win the championship?

Reason for winning: make good use of your strengths to deal with your opponent's weaknesses.

Tian Ji often raced with the sons of Qi State and made huge bets. Sun Bin found that their horses were all about the same strength, and the horses were divided into upper, middle and lower grades. He said to Tian Ji, "You bet big, and I can let you win." Tian Ji believed it, agreed to him, and made a bet with the King of Qi and his sons.

The game is about to start. Sun Bin said, "Now deal with their superior horse with your inferior horse, their middle horse with your superior horse, and their inferior horse with your middle horse." After three games, Tian Ji lost one game and won two games. Finally, he won a bet with the daughter of the King of Qi. So Tian Ji recommended Sun Bin to Qi Weiwang. Qi Weiwang asked him about the art of war, so he regarded him as a teacher.