Strauss and his team endured a torrid day in the field at Newlands
Captain Andrew Strauss insists England are heading in the right direction despite being thrashed by South Africa in the third one-day international.
On a Newlands ground favourable to teams batting first, the hosts posted 354-6 while England made 242 in reply.
The series is now tied 1-1 with the fourth match taking place on Sunday.
"You're going to have frustrating days like this but I still strongly believe we're going in the right direction," Strauss told BBC Radio 5 live.
"We've always said, to get better at one-day cricket is a long-term procedure."
England went into the match in Cape Town having won the previous six completed meetings in the one-day format against South Africa, the latest being the impressive seven-wicket win in Johannesburg last Sunday.
However, Newlands is notorious as a ground on which the team batting first have the favourable conditions and in 20 of the last 25 day-night one-dayers the side setting a target have been victorious.
This, combined with an extremely flat wicket and a South Africa side firing on all cylinders, has convinced Strauss that it would be unfair to judge the side's one-day improvement on this result.
It was a good week training, the guys really knuckled down. We played really good, intelligent cricket tonight.
"It was an exceptionally flat wicket and really good to bat on," admitted Strauss.
"All credit to South Africa, they played really hard from the top. AB de Villiers played a sensational knock and it was tough for us to bowl dot balls and build up any pressure.
"Sometimes you've got to take your hat off to the opposition and say well played."
South Africa's total of 354, to which De Villiers contributed a fantastic 121 in 85 balls and Hashim Amla made 86, equalled the record one-day total for a side at Newlands.
England were able to stay in touch with the required run-rate, thanks largely to 86 from Paul Collingwood and 45 from Kevin Pietersen, but as Strauss admits, the loss of regular wickets at crucial times cost the side.
"It was always going to be difficult to chase that but we felt we had a chance," explained Strauss.
"We got off to a good start and our run-rate throughout the innings wasn't too bad but we lost too many wickets at regular intervals."
Despite the heaviness of the defeat, Strauss feels that the side can take many positives away from the performance.
He was particularly pleased to have Stuart Broad and Graeme Swann back in the side.
Broad looked rusty having only just recovered from a shoulder injury but took 4-71 in his 10 overs.
"Stuart Broad did some really good stuff," said Strauss
"He looked like he had no ill-effects from his shoulder injury which is encouraging and it was good to have Graeme Swann back in the side as well."
The captain also defended his decision to open the batting with Luke Wright, who failed to provide the impetus his promotion was designed for and both batsmen fell for just 24.
"If we were going to chase the total down we needed to be up with the rate or ahead after the first 15 overs as later on at night here it becomes harder to score so it was a risk that didn't really come off," admitted Strauss.
England now head to Port of Elizabeth for the fourth one-day match and Strauss made it clear that they will regroup and come out fighting.
"The Port of Elizabeth game is massive," he said. "We'll fly there tomorrow, have a bit of a debrief and there'll be a lot of positive English cricketers playing on Sunday."
South Africa captain Graeme Smith was delighted to see his side win for the first time in seven against England and hopes the victory will kick-start a run of their own.
"It was a good week training, the guys really knuckled down," he said. "We played really good, intelligent cricket tonight.
"We managed to put it together and AB really came to the fore.
"It's nice to get the whole package together - now we need to get the consistency.
"Hopefully we can build on the success. We'd like to play well on Sunday."