"His integrity and hardwork has brought him this far. His delivered at every level. He used to come alone for practice and run 10 kilometres every day," said Rastogi referring to Kumar's success in the international circuit.
"He needs to maintain and deliver his bowling skills accurately. However, he should not experiment too much and adopt too many new things. He needs to just stick to his strengths," Rastogi added
The bowler from Meerut had a dream debut in ODI, when he dismissed Mohammad Hafeez of his very first delivery. Even in the second Test agaist Australia, Kumar broke through the Australian top order on a pitch which was known to favour the spinners.