Gambhir turned 33 Tuesday.
"And a very happy birthday to my main man…@GautamGambhir u are a rockstar. Stay healthy and happy my friend. Love you," tweeted SRK - the co-owner of the Kolkata franchise.
The left-hander is regarded as one of the most successful Indian openers having played 147 ODIs, 56 Tests and 37 T20s.
He has nine Test hundreds to his name and averages 42.58 in the format while in the 50-over format, Gambhir has hit 11 centuries, scoring 5,238 runs at an average of 39.68.
Along with Delhi teammate Virender Sehwag, Gambhir made one of the most formidable opening partnerships in world cricket.