"We committed the cardinal sin of losing two in players in one over and the allowed India to build pressure."
The 23-year-old Chahal became only the second bowler in T20 cricket to get six wickets in an innings.
Root's LBW during the last over paved way for India's return in series.
Before the match, Kohli had led India in 19 international games at home without a defeat.
India looks to keep the two fresh for the Test series against Australia.
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