Jos Buttler admitted that England had “potentially” made a mistake when choosing to bowl first on the way to a 229-run thrashing by South Africa at the Wankhede, before conceding his team will likely need to “win every game from here on in” to keep their World Cup defence alive.

Asked to bat first in Mumbai, South Africa piled up 399 for 7 during their 50 overs despite losing a wicket to the second ball of the innings, with Heinrich Klaasen’s 61-ball hundred building on top-order half-centuries from Reeza Hendricks and Rassie van der Dussen. Marco Jansen also struck 75 off 42 balls as he and Klaasen added 151 in 12.4 overs for the sixth wicket.

By that stage, England’s players were visibly wilting in the heat. The bowlers made regular trips off the field, with Adil Rashid suffering from an upset stomach and David Willey felled by cramp during one over. In addition, Reece Topley suffered a suspected broken finger when fielding the ball in his follow through, and had to leave for treatment with one ball of his fourth over unbowled.

When asked at the post-match presentations whether bowling first was a mistake, Buttler said: “Yeah, potentially. You always look back and reflect on the decisions you make. Obviously incredibly tough conditions here in the heat, we saw that with the boys in the field. Everyone put in a great shift. I still believe if it was 340-350 and we got off to a good start it would have been a great chase. But yeah, potentially should have batted first with the heat.”

Aiden Markram, standing in as captain for South Africa due to Temba Bavuma suffering from illness, said they had been “slightly” surprised by Buttler’s call. “We know England do like chasing,” he said. “We were going to bat first. Happy that it worked out the way it did, we felt comfortable doing that and I think it helped us a lot that our big quicks weren’t in the sun cooking.”

Although Topley returned to deliver another five overs with a strapped finger, he looks set to be ruled out for the rest of the tournament. With three defeats in their first four matches, the defending champions are already in a struggle to qualify for the semi-finals via a place in the top four.

“It leaves us with no room for error, we have to probably win every game from here on in,” Buttler said. “That’s the situation we find ourselves in.”

England made three changes for the game, having suffered a shock defeat to Afghanistan in their previous outing. Ben Stokes was fit to make his first appearance of the tournament, while Willey and Gus Atkinson both made World Cup debuts, as Liam Livingstone, Chris Woakes and Sam Curran made way.

Buttler denied that the changed personnel contributed to England’s poor showing, as South Africa recovered from losing Quinton de Kock early to post the second-highest total of this edition of the World Cup.

“I don’t think so. Throughout the first innings, lots of things didn’t quite go to plan. We started nicely, [but] Reece picked up that injury and then the unknown as to whether he’d come back or not, trying to fiddle a few overs in. Those kind of things, couple of guys struggling with the heat, etc. So it was a tough 50 overs there, the boys fought hard, a lot of effort.

“I thought if we could have restricted them to 340-350, probably on this pitch it would have been a really good chase. They just got away from us there at the end.”

Having been baked out in the middle during the hottest part of the day, England were quickly cooked during their chase, slipping to 38 for 4 inside the powerplay on the way to their heaviest defeat by runs in ODIs.

“[It was] certainly tough, the humidity and the cramps and all the other challenges – yeah, it was tough,” Buttler said. “We needed to get off to a really good start, chasing a score like that. The ball did a bit, a couple of dismissals, caught down the leg side, caught leg slip – when those kind of things start happening you feel like the writing’s on the wall a bit.”