Gambhir completed his 3000 runs in One-Day Internationals during his splendid innings of 150 not out that saw India outclass Sri Lanka by seven wickets in the fourth match and seal the five-match series 3-1 with a match to spare.
"Gambhir has been improving a lot. Gambhir is a cool headed guy. He has been scoring runs and he is getting them consistently," Ganguly said in Kolkata on Thursday.
It was for the first time after his international retirement that India played at his home venue.
Asked whether he missed the on-field action, Ganguly said, "Not at all. I am enjoying my life."
A charismatic leader during his time, Ganguly said his retirement decision was correct as the battle of making a comeback and getting dropped again and again was becoming tough.
"It was getting enough. Making a comeback every time after getting dropped. How many more times would I have fought to make my way into the side? This battle was getting tough. There is a limit to it," said the left-hander, who came to watch the match with his wife Dona and daughter Sana.
Ganguly also felt that dew played a role in Sri Lanka's defeat, saying," The balls skid as it becomes difficult for bowlers to control the ball. I knew it would be easier to bat second."
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