The Blues host Spurs at Stamford Bridge in a fixture that is likely to play a pivotal part in both team's quest for a Champions League place, and Mata has admitted that Bale has the ability to have a decisive impact on the match.
The 24-year-old wrote in his blog, grada360.com: "We are aware that there's still a job to do. Obviously, it's a vital game for both teams and we will have to watch one of the best players in the world: Gareth Bale.
"He is in an amazing shape and proves to be a decisive player for Spurs almost every week. I take this opportunity to congratulate him for all his recent awards."
Mata's netted with a deflected effort to earn Chelsea a late 1-0 victory over Manchester United on Sunday.