Fiji boss Jake White (left) believes Andy Farrell (right) and Ireland must improve before facing South Africa
Former South Africa head coach Jake White said his Fiji side "did Ireland a favour" in Saturday's Nations Championship contest before the Irish face the Springboks in Dublin next week.
Fiji lost 43-15 to Ireland at Aviva Stadium having frustrated Andy Farrell's side during a closely contested first half.
While Ireland scored 26 unanswered points in the second half, White - who led South Africa to World Cup glory in 2007 - suggested Farrell's team cannot afford similarly sluggish spells against the back-to-back world champions, who won 24-13 in Dublin last year.
"We were playing a little bit like South Africa to be honest, I think that sums it up," said the 62-year-old.
"We were letting Ireland have the ball and we were happy to defend against them and we were happy for them to try to outwork us."
Asked to assess Ireland and South Africa's highly-anticipated meeting on Saturday (16:40 GMT), White added: "Well, I think we probably did Ireland a favour today.
"Let me put it that way, because I think Ireland deep down know that if they play like that against South Africa, they're gonna be up against it."
Ireland score seven tries in victory over Fiji in Dublin
Ireland shake off sluggish start to brush aside Fiji
White, who was appointed Fiji boss last month, was frustrated that his side opted to take a tap penalty instead of a scrum when the game was in the balance in the second half.
"I know how South Africa operate and they would've taken that scrum there, they would have backed the fact that they wanted to get [Ireland] a yellow card," said White.
"They would have taken another scrum and another scrum and another scrum, and they wouldn't have worried about the ref making a call about collapsing or early engaging.
"The five-metre line-outs that we didn't take opportunities in, and the five-metre scrum and tap penalties, South Africa will turn those into points and I'm sure that Andy [Farrell] and the players will be aware of that.
"They [Ireland] have been around a long time, and they know what's coming, and that's probably why he picked the team that he did because he wanted to make sure that they get a little bit more gun-ready for next weekend, because the easiest thing would have been to change the team and then they're probably one game shy of playing South Africa next week."
White added: "If I'm coaching South Africa and Malcolm Marx is standing there [as captain], there's no way he is going to say, 'we'll take the tap'. There's no way that happens.
"Malcolm Marx will say, 'let's take the scrum,' or 'we'll kick it out into the corner and we'll take the line-out'. And that's because they back themselves in those situations."
A short but sweet Ireland cameo for James McNabney
When White's comments were put to Farrell, the Ireland boss said: "We were just saying in the changing rooms that we learned some good lessons and we'll use them in the right manner for next week."
Farrell also admitted the scoreline flattered his side after they pulled clear having only led 17-15 at the break.
"Pleased to get the win, especially the scoreline, it flattered us a little bit but having said that you've got to work for those points and after 25 minutes you're down by five points against a side that's playing pretty well," said Farrell.
"As far as the physical nature of the game, I thought they were winning collisions, they were good in the air and on the floor, running really physically through the line and the breakdown was pretty good.
"All in all, we need to understand that wins here when you're under a bit of pressure, they're all pretty precious."
While Ireland struggled to click at times, Farrell was impressed by James McNabney's shorter-than-expected debut.
The Ulster back row came off the bench and made two huge carries before being forced off with a head injury which rules the 23-year-old out of featuring against South Africa.
"He's joking in the changing rooms - he's delighted with himself for the shortest cameo of a first cap," he said of McNabney.
"I reckon it's the best cameo of three-and-a-half minutes or whatever it was on a debut in Irish history really.
"He remembers the two breaks that he made, so he seems in good spirits."
