England captain Owen Farrell wants his side to learn lessons quickly in order to turn around a five-match losing run.
The touring England team threw away a 12-0 lead to concede 23 unanswered points to South Africa on Saturday, extending a miserable run in Test matches.
There is plenty of room for improvement ahead of the World Cup next year, but Farrell does not want to have to wait that long to see a change in England's play.
"We lost momentum in that second half," he said after the match.
"We'll have to make sure we look back at it and see where we went wrong, but there were some big moments in that game where we weren't composed enough and we will have to learn from it.
"We want to learn our lessons now. I know 2019 is part of the big picture, but we want to learn our lessons now and start winning now. We're going to have to re-group for next week."
There are changes to the squad ahead of the third and final match of the series, with Ellis Genge (knee) and Mako Vunipola (family reasons) travelling back to England. Exeter Chiefs' Alec Hepburn has been called up.