Root’s 113 steered England to an 86-run victory at Lord’s on Saturday as Trevor Bayliss’ men squared the three-match series.
India’s limp response of 236 all out in their full 50-over allocation handed England a comfortable win that had appeared at best in the balance at the interval.
David Willey fired a vital unbeaten 50, with captain Eoin Morgan adding 53 as England retained their status as the world’s top-ranked ODI side.
“The pitch was always going to deteriorate quite quickly,” said Root.
“That ruthless side of the ODI team really came out today. And we’re seeing it more and more.
“Hopefully we can back that up and finish the series off now.
“David came in and took a lot of pressure off me, to help us turn in what was at least a par score, so it was a fabulous effort from him.”
Root had faced just three deliveries from Kuldeep Yadav before Saturday, with England struggling previously to decipher the 23-year-old’s left-arm wrist spin.
Kuldeep stunned England with his match-winning 6-25 at Trent Bridge on Thursday, but come the weekend in London the hosts felt they had a better handle on his approach, even though he still claimed three wickets.
“Ultimately you’ve just got to trust your game and trust your technique; I felt I was picking him OK,” said Root.
“It was more about spending time out there and trusting the way I go about things.
“I feel I’ve got a solid approach against spin bowling.
“Having a few overs under my belt today gave me quite a lot of confidence.
“It’s just one of those things, when you don’t spend the time you might like out there on occasions and it happens a few times you’ve got to make sure you stay strong and trust what’s served you so well for such a long time.
“It was a chance to pick as many cues up as possible throughout this innings, to make sure I don’t get caught cold in Leeds.
“On a turning surface it’s important to make sure you feel you’re playing it in the right manner and working things out.”
Relieved to have posted his first ODI century since March, Root added: “I’m just desperate to contribute to us winning games of cricket.
“Thankfully I managed to follow through here. I thought we were quite smart in getting to what we thought was a good total; we didn’t go too hard too early.”
India were left to rue a curiously subdued innings from veteran MS Dhoni, who laboured to 37 off 59 balls and was booed by sections of the Lord’s crowd.
The tourists skipper Virat Kohli defended Dhoni however, insisting India still believe in their high-profile wicketkeeper batsman.
“This comes up again and again when he is not able to play in the normal way he does,” said Kohli. “It’s very unfortunate people just jump to conclusions very quickly.
“When he does well people call him the best finisher ever and when they don’t go well they all pounce on him. We all have bad days in cricket and today was a bad one for everyone, not just him.
“Other people jump to conclusions but we don’t, we totally believe in him.”
from their full 50 overs.
England chose not just to bat first – for the first time since October 2016 – but also to keep their biggest hitters in reserve and away from Kuldeep. The 23-year-old slow-bowling star bagged 3-68 at Lord’s, uprooting key men Jason Roy, Jonny Bairstow and Eoin Morgan, with the captain notching 53.
Ben Stokes and Jos Buttler joined the fray down the order, with England’s plan clearly for both men to make hay against anyone other than Kuldeep.
Instead both heavy hitters holed out cheaply elsewhere, left to kick themselves for missed opportunities.
Neither need have worried as, first Root and Willey steered England to 322-7, and then Indiafailed to do anything with their innings.
Credit must go to England for tight bowling and the Yorkshire pair of Liam Plunkett, who took 4-46, and Adil Rashid (2-38) as England restricted an oddly subdued India to 236 all out
Mark Wood set England rumbling towards victory by skittling Rohit Sharma’s stumps with the in-form opener departing for 15, before Willey forced Shikhar Dhawan to edge to Stokes for 36.
Plunkett then had Lokesh Rahul caught behind for a duck to leave India 70-3. Kohli was trapped lbw by Moeen Ali, before Rashid bowled Suresh Raina for 46.
Hardik Pandya made a quick-fire 21 only for Plunkett to draw him into edging behind, and then Rashid snared Umesh Yadav for a duck, stumped by Buttler.
MS Dhoni’s interminable 37 came to an end when he skied one off Plunkett to Stokes. Yuzvendra Chahal then dollied the match’s final ball from Willey straight to Stokes.