Tevez arrived at the Juventus Stadium in a reported €10million (£8.2m) deal from Manchester City in the close-season, and has responded with 18 league goals in a fruitful debut campaign thus far.
And Juve captain Buffon believes that the Argentina international's desire for victory has been crucial this term, particularly at the start of the season.
"I have to say that in key moments of the season, in my opinion, the will to win and the characteristics of a driver like Carlos Tevez has given us a big hand, especially at the beginning, when we were a bit apathetic," he told Sky Sport Italia.
"His great physical prowess, although he is not enormous, his competitive spirit, in many games, especially at the start, dragged us [through] and earned us the three points."
Juventus are seemingly on their way to a third straight Serie A title, and hold an eight-point lead over second-placed Roma with just five games remaining.
And Buffon also paid tribute to head coach Antonio Conte for continuing to motivate the team.
"He has brought a lot this year on a motivational level, because it can be argued that after two [titles], the third is not so clear cut because in some groups there can be a sense of fulfilment that can cause issues," Buffon added.
"But someone like him has helped us this year to always stay on track, not to take anything for granted."