England kicked-off against Ireland on Saturday just 80 minutes away from back-to-back Slams and a record 19th successive Test win.
Already assured of the Six Nations title, England kicked-off against Ireland on Saturday just 80 minutes away from back-to-back Slams and a record 19th successive Test win by a major rugby union nation.
But at a rainswept Lansdowne Road, they were both out-thought and out-fought by Ireland, who won 13-9 and scored the game's only try through lock Iain Henderson.
The result meant England had suffered their first defeat under Eddie Jones but the Australian has always made it clear his ultimate goal with the side is to win the 2019 World Cup in Japan.
Nevertheless, experienced back-row Haskell felt England were now a better team than a year ago for all that they failed to surpass world champions New Zealand's record of 18 consecutive Test wins.
"I believe so," he said. "You can't win everything in rugby, you can't win forever.
"No side in the world has done that, not even all the All Blacks," added the 31-year-old.
"You have days like this. If you've got a long-term project, which Eddie and his coaching staff do for 2019," explained Haskell, a veteran of 75 Tests.
"This is a dry run for other things to come. We've just got to learn from it."
Indiscipline cost England on the rare occasions they generated momentum against a ferocious Ireland, the boot of fly-half Jonathan Sexton punishing them with penalty points or kicks deep into their own half.
For Haskell, one of five survivors in England's matchday 23 on Saturday who also saw their bid for a 2011 Grand Slam evaporate with a 24-8 defeat by Ireland in Dublin, it was all-too familiar experience.
"Credit to Ireland, they were the better team," he said.
"Field position played a big part in that. Every time we got near their half we would cause a mistake, a turnover or something and we would just be back in our half.
"You’ve got to build pressure against a side like Ireland -- and the pressure was all on us," he added.
As happened six years ago, England had the awkward experience of lifting the Six Nations trophy immediately after a defeat.
"I am a very competitive person, I hate losing, I don't like celebrating any loss, but at the end of the day this team has come a long, long way," said Haskell.
"We've still won the Six Nations back-to-back."
One Englishman who played a key role in Ireland's victory was Andy Farrell.
The father of England's goalkicking centre Owen, Farrell senior is now Ireland's defence coach.
He was ditched from a similar position with England in a clear-out of backroom staff following their pool-phase exit on home soil at the 2015 World Cup -- a shake-up that paved the way for Jones to replace Stuart Lancaster as head coach.
"He's a legend of a guy and a fantastic coach," said Haskell of Andy Farrell.
But Haskell added that player discipline rather than coaching input was a key factor in matches between leading nations.
"It's just down to whether teams have the discipline to play in the right areas," he said.
"You can't build any pressure if you keep turning the ball over or keep giving penalties away."
Ireland, who ended the All Blacks' winning streak at 18 with a 40-29 victory in Chicago in November, boast a formidable home record.
They've yet to lose a Six Nations match at Lansdowne Road under Kiwi coach Joe Schmidt and have been beaten just twice in their last 18 internationals at the ground.
"We talked all week that it wasn't about stopping them (England) doing anything," said Ireland captain Rory Best.
"It was about us producing a performance that was worthy of this team, worthy of this crowd and worthy of this occasion," he added.