India fast bowler Ishant Sharma gave credit on Friday to Zaheer Khan for saving his career. The 22-year-old fast bowler took a career-best six for 55 in the second Test against West Indies on Thursday at Kensington Oval, becoming the fifth youngest bowler to capture 100 Test wickets. \"I am thankful for Zaheer always stressed to me the importance of fitness,\" said the wiry fast bowler. \"I never took it seriously. Now I realise how important it is for a fast bowler to be fit. \"I also tried to copy someone else, and it affected my pace and rhythm. \"From (the last) IPL onwards, I began realising why my body tires, how it recovers. With so many matches and travelling around, I learnt how to train and give of my best.\" Sharma now has 102 wickets at an average of 33.36 from 33 Tests, and he rated his spell performance as one of the most important, helping India to grab an 11-run, first innings lead over the hosts. \"I know now how to work on each batsmen, what to bowl, how to accept situations, conditions and opponents,\" he said. \"I like Test cricket because you could always come back. If you haven\'t bowled the first spell well then there are second and third spells. \"I also know there are bound to be ups and downs in a sportsman\'s career. \"In a small career, I have seen so many ups and downs. When you are down, nobody asks you.\" Sharma said he hoped his performances on the tour so far would justify a recall to the Indian limited-overs squad. \"In one-day cricket, how to bowl in the powerplays and slog overs require clever bowling,\" he said. \"I was never that clever before. Now I know my bowling, and want to make a comeback in the one-day arena.\"