Dubai: New Zealand’s tight Rugby Championship wins over Australia and South Africa show the gap at the top of world rugby is narrowing, according to former All Blacks coach Sir Graham Henry.

The Kiwis scraped a 35-29 win at home to Australia in August having earlier trounced them 54-34 away, and then beat South Africa just 25-24 away on Saturday following an earlier 57-0 thrashing, to claim their fifth Rugby Championship in six years.

They have now been World No. 1 for almost eight years, winning two World Cups within that time in 2011 — under Henry — and 2015.

But have recent defeats to Ireland and the British and Irish Lions — the only blemishes in the last 32 matches — shown their dominance is on the wane?

“Possibly, nobody has got the prerogative to be the best in the world forever, and nobody can guarantee continued success,” said Henry, on the sidelines of the Emirates Airline Dubai Rugby Sevens Long Lunch at the Crowne Plaza in Dubai’s Festival City on Thursday.

“I don’t think the gap is too big, which is what rugby needs, it doesn’t need one side that’s unbeatable because that’s boring.”

Explaining the improvement of Australia and South Africa from their first game against New Zealand to their second, he said: “There are a number of factors, there is no greater motivation than getting beaten badly. If you’ve any backbone at all you’re going to get up for the next one.

“Australia and South Africa had fallen away pretty badly in recent times but it was good to see great contests and superb rugby in the last two fixtures. I think that’s pretty pleasing and obviously the cultures of South Africa and Australia are getting stronger and that’s good for rugby.”

So, can anyone stop New Zealand from retaining the World Cup in 2019?

“Yeah, for sure, England are obviously on a bit of a roll, they’ve only lost once since Eddie [Jones] has been coach, against Ireland this year.

“The World Cup is two years away and I was pleased to see Australia and South Africa improve a little during this series. Going into the next World Cup obviously the All Blacks will be favourites but England, Ireland, Australia and South Africa, and all the old enemies will all be up there.”

England play New Zealand next year so how might that fixture affect New Zealand’s psychology going into the World Cup if they lose against the World No. 2s?

“I think the loser has the advantage in that match. We had games we sacrificed because the World Cup was more important,” said Henry referring to his reign as coach from 2004 to 2011. “Going into the 2011 World Cup we lost to Australia but beat them in the semi-final. It gives you the edge, because they beat you last time, to be the best you can be going onto the field. That game between England and New Zealand is probably 50-50 but I don’t think it’s a disadvantage for whoever comes second in that fixture.”