Former British and Irish Lions head coach Sir Ian McGeechan believes England are two years behind world champions New Zealand despite their 3-0 series whitewash of Australia.
Saturday's 44-40 victory in Sydney made it nine straight wins for England since Eddie Jones was appointed head coach in November following their group-stage exit from the World Cup on home soil.
England end a season in which they won the Six Nations Grand Slam placed second in the world rankings, but McGeechan feels the gap to the all-conquering All Blacks, who have just completed their own clean sweep of Wales, is considerable.
"There is no doubt that England have been absolutely outstanding in winning 3-0 in Australia," he wrote in the Sunday Telegraph.
"It is a magnificent achievement, but the truth is that they are still some distance behind New Zealand.
"In fact, I would say they are two years behind the world champions."
McGeechan has encouraged England to work on getting the ball wide and to recognise mismatches quicker.
"I think that in two years' time, Jones will be looking to have found an influx of speed, accuracy and intent that can be put into England's game so that they have the numbers in the outside channels to do some serious damage," he added.
"It is not inherent in the players. Jones is going to have to put it there and give them an England mindset that grows every time they come together.
"England are clearly above Australia and South Africa now, Ireland have made history and Scotland, despite not overly impressing, have won two Test matches, but New Zealand are still some way out on top."