Eoin Morgan says England's one-run defeat to South Africa was "a great game to play in" as they build towards the T20 World Cup in October.
A brilliant final over from Lungi Ngidi helped the hosts edge a thrilling contest with England squandering a commanding position at East London.
However, Morgan believes these are just the type of matches his side need in preparation for a global tournament.
"I definitely think we could've [found an extra run or two], I thought particularly during the chase we were in a very commanding position," he told Sky Sports.
"We never through a cluster of losing wickets, Jason (Roy) and myself established a partnership quite well with the new guys coming in and with the short boundary one side, we never really looked flustered - probably until Ngidi came on in the 18th and probably the last over that he bowled turned the came on its head.
"Even in a position needing seven off the last over with new guys coming in, we'd have expected to win that game.
"It's a great game to play in because you get a feeling of where guys are at, they're put under pressure, you get to see what skill-level they produce, how their temperament is. So in terms of actually improving in that position, I think it is great for us."
England have just eight T20 matches between now and the start of the tournament in Australia and as such Morgan taking the series with South Africa very seriously.
"I think they're really significant," he said. "We've nine (sic) more games between now and the start of the World Cup so getting guys in positions where they're hopefully going to bat in the middle of October is extremely important, because when the pressure is on you find out more about guys and where they're at.
"If you've got guys playing in positions they don't know inside out then they get exposed. I sort of go back and look at the 2016 T20 World Cup where we were beaten in the final in dramatic fashion and what we learnt and grew from there.
"We took a lot of confidence from going into the tournament as a bit of an afterthought and learning as much as we can. We were beaten in the last over but, actually, trying to improve our game so if that happens again, we're in a better position to counter anything that happens. We'd like to be in a better position going into Australia than we were in India and hopefully we might be contenders."
England must win the remaining two games to take the series and Morgan is confident his side will bounce back quickly.
"One of the big things in our changing room is that we learn quite quickly from each other," he added. "We're very open and there's not massive egos around so we can say 'I struggled today, what did you look to do? How were you effective? Teach me, can we spend 10 minutes doing it?'
"Or it might be a mindset of going and taking that risk earlier than you probably should. So they'll be a little bit of that over the next 24 hours, a little bit of looking at the footage to see where our accuracy levels were with the ball, me with field settings and then just being more clinical with the bat.
"But full credit to South Africa, they clawed their way back into a game that I thought we easily should have won, but we didn't. Fair play to them."
Watch the second T20I between South Africa and England from 3.30pm, Friday on Sky Sports Cricket.