Gambhir, 29, feels Kirsten's presence in the India dressing room has done a world of good to his game as he has given him a lot of confidence.
Kirsten, who joined the India team in March 2008, carried it to the top of Test rankings, and Gambhir says he is one of the players to prosper in the process.
"Kirsten worked on my game, he has helped me a lot. Unlike other coaches, he has never asked me to make changes in my game. Importantly, he understood me both as a player and person," Gambhir
"Kirsten worked on my basics and tried to improve on them. It was quite encouraging coming from a person who has played 100-odd Tests."
The left-hander, who made his debut in 2004, had only one Test century to his name till 2007, but hit two more and a double century in 2008 and four centuries in five Tests in what turned out to be an incredible 2009, the year in which he was voted the International Cricket Council (ICC) Test Player.
Gambhir, who returned home after the South Africa Test series following a hand injury, said Kirsten, himself being a left-handed opener, worked on key areas to better his performance.