Nat Sciver has attributed her match-winning 27-ball 55 in England's win in the rain-affected first T20I against India to her "boundary-oriented" approach on a pitch that had their openers struggle for fluency early in their innings.

"[It] Felt good. I wasn't thinking about the speed of it," Sciver said after hitting the joint-fastest T20I fifty - off 24 balls - by an England Women player, in Northampton on Friday. "When I did get the strike, I was thinking quite boundary-oriented.

"I knew the wicket was quite good and that with their batters we needed to get a good score. It was good to bat through the innings and then get a partnership with Amy [Jones] to get us up to a good total."

Sciver struck eight fours and a six in her 27-ball stay, having slotted in at first-drop. Rapidity and ease at hitting boundaries were the dominant themes of her innings, thrown into sharp relief by openers Tammy Beaumont and Danni Wyatt, themselves seasoned big-hitters, playing out the first three overs without any boundaries.

"[…] I managed to get my first ball away for four," Sciver, the Player of the Match, said. "That doesn't happen often. It felt good, so I just went on from there and gathered a bit of momentum for my innings.

"I guess after about the first four I felt comfortable at the crease. Obviously, I was watching Danni and Tammy bat and they hadn't quite got one out of the middle to feel comfortable. They would have been swaying just getting used to the pace of the wicket. But I knew after I hit that first ball I would be able to hit through the line of the deliveries and was able to use my feet.

"I don't know, sometimes people come in... I mean, someone else could have come in and made the wicket look as easy as that. I guess it's different for different batters on the same day. I knew when I had hit that, that we should get a few more runs than we were heading towards. I was happy me and Amy played in similar ways on that wicket and were able to get a partnership together."

With No. 5 Jones, who started off cautiously before motoring to a 27-ball 43, Sciver stitched a quickfire stand of 78 off just 42 balls, propelling England to 177 for 7 in their 20 overs. Between them, Sciver and Jones struck 12 fours and three sixes, with both exuding enviable ease especially against the four spinners India deployed, as well as medium-pacer Arundhati Reddy.

The pair struck three fours apiece in the 15th and 16th overs - first Jones off left-arm spinner Radha Yadav and then Sciver off Reddy - as India conceded 16 runs in each of those overs.

"I just spoke about feeling comfortable at the crease, really," Sciver said when asked about the discussion that ensued after Jones joined her following captain Heather Knight's dismissal. "Luckily, I managed to feel comfortable quite quickly, but other batters might have taken a bit longer, but as soon as you get the pace of it, you can hit though the line. Yeah, she really accelerated towards the end of her innings, which was brilliant."

Sciver also led the charge in England's formidable returns against wristspinner Poonam Yadav. Having been dropped for the last two T20Is in the three-match home series against South Africa earlier in the year, Poonam, India's highest wicket-taker in T20Is, picked 4-0-32-1. She, however, showed diminished efficacy in containing the opposition as well as taking wickets, as has been the trend in her performances this year.

"It [Poonam's bowling] is something we've been mindful of over the last couple of years, back in the [2018] T20 World Cup as well," Sciver, who shuffled deep into her crease and came down the pitch at will against Poonam, said. "She, obviously, bowls very slowly, but I guess my strength in general, off spin, is back-foot [shots] and to be able to read it whether or not it's short enough for me to get onto the back foot - it's important as well as meeting the ball when you can on the front foot. We've faced her a lot and done quite a bit of homework on her. Think we played her pretty well today."

Asked about her unflustered demeanour that has become a standout trait in her batting performances over the recent past, Sciver said: "It's been quite natural. People have always said I've got a presence at the crease, so I guess that helps. I can really be like that but be flustered inside if there's a lot of pressure or [I] haven't got off to a good start. It's not always the same inside, but yes, I'm lucky, I guess."

Though rain cut short India's chase in the ninth over, Sciver made an imprint with the ball, too, to help set up an 18-run win. Opening the bowling with fellow quick Katherine Brunt, Sciver had Smriti Mandhana pull a short ball straight to deep-backward-square leg for 29 off 17 just as India's second-wicket stand had begun to gather pace.

"In T20Is over the last couple of years, I've had a bit more responsibility in the powerplay," Sciver said. "I guess it started when Katherine had to go home in the T20 World Cup in the West Indies [because of injury], so I got a chance to open then and I think I've done all right. It's good to open again.

"It's good [to be opening the bowling with Brunt]. I think we did it in New Zealand in a 50-over match [earlier in the year]. It's a different role but one I like and enjoy, so being able to swing the ball is really good. And when you have Katherine taking the wicket of Shafali [Verma] at the other end, that's excellent.

With England taking an unassailable 8-4 lead on the points table in the multi-format seven-match series, Sciver said the hosts' performance on Friday could lay down the marker for the remaining two T20Is.

"It's always important for us to start the series [well], so the change of format is included in that and we hit the ground running today," Sciver said. "With the change of format, it was important for us to not ease into it and put things to right that maybe we didn't do so well in the last ODI match. It's a format we're quite comfortable with. In terms of plans, they are very strong in people's minds, so when it comes together like that, it's good."