Junior Springbok coach Kevin Foote has identified the impact of his replacement bench as the decisive factor in Sunday's Junior World Championship semifinal comeback against England, with South Africa overturning a 12-20 halftime deficit to book a Final berth against France.

The Junior Boks trailed by eight points at the break despite England having been reduced to 14 men following a permanent red card to Seb Kelly for headbutting fullback Luan Giliomee. South Africa then scored four tries in an 11-minute burst after the interval to effectively end the contest.

Foote deployed a six-two forward-heavy bench split and had all his replacement forwards on before the hour mark. Props Oliver Reid and Siphosethu Mnebelele were among those introduced during that scoring surge, and the pack maintained the intensity through to the final whistle.

"We have amazing depth. We always said that some guys like Tom [Beling] only played the first game — it's been a long wait, but he came on and did well," Foote said. "JT Orange always had an impact off the bench, the same counts for Liam [Van Wyk], Rambo [Kubheka] and Luan [Van der Berg] — all of them are doing a great job."

Foote also credited the starting forwards for refusing to let their output drop at the five-week mark of the tournament. "It's now game five and week four, so everyone will be feeling it, so the fact that the forwards kept going and didn't drop any intensity is very inspirational."

On the halftime message, Foote kept it simple: "It was just about us looking after the ball better and ensuring we put consistent pressure on England and not take the pressure off if we make our own mistakes."

South Africa now face France in Saturday's Final, with the Junior Boks chasing back-to-back titles — a feat that would be a first in the competition's history. France qualified by defeating New Zealand in the opening semifinal.

"They scored and hung in right until the end against New Zealand. That shows their spirit — they won the U20 Six Nations, so they will be up for this," Foote said. "We'll recover now, enjoy the week together as our last time as a group together, and we're looking forward to Saturday."