Previous Sri Lankan sides have found early season conditions in England not to their liking but the reigning World Twenty20 champions showed few signs of discomfort in seeing off England -- the only team that beat them on the way to the title in Bangladesh this year -- by nine runs at The Oval on Tuesday.
They return to the south London ground for the first of a five-match one-day international series on Thursday where the likes of all-rounder Thisara Perera and slingshot seamer Lasith Malinga will be keen to repeat their success in Tuesday's match.
"We needed that win to tell ourselves we are good enough to compete against these guys on their home soil."
England are still struggling to come to terms with their 5-0 Ashes defeat in Australia and, with the return of Peter Moores as coach allied to several backroom and personnel changes, are far from being a settled side.
More From This Section
"From England's point of view, they have gone through a couple of shaky series and have a new management and a couple of new players," Atapattu said Wednesday. "They could be different in their approach.
Atapattu used to bat with dynamic Sri Lanka opener Sanath Jayasuriya, whose whirlwind approach revolutionised the way teams went about run-scoring at the start of a one-day innings.