Captain Michael Vaughan hailed a new peak for England after their crushing victory over South Africa in the NatWest Series final.
England move to third in the world rankings
The series victory, achieved with a seven-wicket win at Lord's, moved England to third in the world one-day rankings.
England's third win over the tourists in four matches, and the second straight after a four-wicket win under lights at Edgbaston on Tueday, sets them up well for the forthcoming Test series.
The hosts bowled South Africa out for 107 and then raced home in 20.2 overs with Vikram Solanki cracking a rapid 50.
"I thought we were hugely impressive at Edgbaston on Tuesday but we beat the lot today," said Vaughan.
"We put the ball in the right areas and set the tone. We took wickets at the right times, they kept snicking them, Chris Read caught them and for Vikram to go out and bat like that was superb.
"South Africa have given us some tough games and I'm sure we are going to have a tough Test series against them."
The first of five Tests begins at Edgbaston on 24 July.
Darren Gough gained the man-of-the-match award after returning figures of 2-9 from seven overs.
Gough has been impressive throughout the series after finally overcoming a knee injury but was non-committal on whether he was physically ready to make his Test comeback this summer.
"I just want to enjoy my cricket and see what happens. Who knows?" he said.
"I'm pleased to be back. It was probably the worst I'd felt for rhythm in my first over but once I got going I was fine.
"It was a great team performance. We put it in the right place and made them play."
South Africa captain Graeme Smith admitted that nerves may have got the better of his side, who were shot out for their lowest total against England in their first ever one-day international at Lord's.
Solanki completely dispensed with cross-batted shots and played beautifully
But he claimed the way the side had performed in the series was a "good stepping stone for the future".
"We can take a lot of hurt out of this and hopefully turn that into a positive for the Test series," Smith added.