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In Test Cricket, it was Andy Flower who scored 232 not out of 444 balls in 544 minutes against India at Nagpur
In ODIs, it is undoubtedly Mahendra Singh Dhoni who compiled a fantastic 183 not out of 145 balls against Sri Lanka in Jaipur
In T20s, it is Brendon Taylor of Zimbabwe who scored 60 not out of 45 balls against Australia in the ICC T20 World Cup . The match was played at Capetown.
It is interesting to note that in Test Cricket and in T20s, it's the Zimbabweans who have reigned supreme whereas in ODIs, Dhoni surpasssed Gilly's score of 172 against Zimbabwe in Hobart with the score of 183 not out.
Gilly holds the second , third and fourth spots in the list of highest individual scores by a wicket keeper batsman while Dhoni comes a close 5th.