South Africa skittled England for 154 on Tuesday and then rattled off the target with more than 30 overs and nine wickets to spare in a match which was effectively a knock-out quarter-final.

"The team is really on a high now, the momentum is good. I think if we had cruised along we might not have had the realities we have had along the way and the thought processes that we need going into the big games," Smith told a news conference..

"Just feeling the atmosphere in the dressing room now it is really upbeat and positive. It is the South African dressing room that I am used to and that will bode well going into the semi-final."

Defeats by Bangladesh and New Zealand in the second round had thrown doubts over South Africa's chances of progressing further.

After sealing their last-four berth, they can now look forward to a likely showdown with holders Australia in St Lucia next Wednesday. Sri Lanka and New Zealand are expected to contest the other semi-final in Jamaica on Tuesday.

Smith hit an unbeaten 89 against England and raised his arms in triumph as soon as he smashed the winning boundary.

"It was pretty emotional at the end of the game; it was such a big game. We were clinical in the field, we built pressure from the start, we got the ball in the right areas and we were so calm and focused," he said.

SUPERB SKILLS

"The way we have played we consistently believe we can beat England and we know we are good one day team.

"With the World Cup, you need a bit of luck. Our skills were superb today and ... we made our own luck and it was nice to get that behind us."

Smith said that he was pleased with the improvement in team morale during the four years he has been at the helm of the side.

"To see the way the guys did it, the character in the side, that is one of the things that has changed.

"It is not a cliche, the guys really do love representing their country. There are always a lot of things said when we lose games but it does mean a lot to these guys and it does mean a lot to be in the semi-finals. Hopefully we can win that big game and come back to Barbados (for the final on April 28) -- that would be awesome," he said.

Swing bowler Andrew Hall was the match-winner with a spell of five for 18 and Smith was full of praise for his team mate.

"Hally's spell with the reverse swing was superb but he was very well backed up by everyone," he said.

Smith said the victory in a must-win match had put to bed the talk of his team as 'chokers' under pressure.

"Today was a big pressure day and I think we really demolished that today. We were superb, the way we went about our business today under pressure was superb to watch," he said.