The Three Lions face Uruguay in Sao Paulo on June 19 and Roy Hodgson will be poring over Northern Ireland's 1-0 defeat at Estadio Centenario for pointers.
And, without the injured Luis Suarez, the Group D opponents showed little to cause the England boss sleepless nights.
La Celeste enjoyed plenty of possession but only breached a depleted Northern Ireland once in the 62nd minute when substitute Christian Stuani finished from close range.
O'Neill was proud of his team's battling effort, in front of almost 60,000 expectant fans, and saw enough to tip an England success.
"Having seen Uruguay, I would expect England to beat them in Brazil," said.
"I think if England play with pace in the forward areas they will cause them real problems
"I'll be honest, I think you can get at them.
"It might be different when Diego Godin comes back but if they can get isolated situations, particularly against Diego Lugano, they'll get some joy.
"I also think they'll get joy through the middle of the pitch with the quality they have and I think Wayne Rooney playing off Daniel Sturridge would give Uruguay a problem.
"This is a good team but it's heavily dependent on the front two, if you nullify them you can get opportunities against them."
O'Neill revealed he had not been in contact with Hodgson prior to the fixture, but would be happy share any observations if the call was made.
"I haven't spoken to Roy in the build-up but if he wanted to call me or my assistant Billy McKinley, who he worked with at Fulham, there'd be no problem there," added O'Neill.
"But I'm sure he doesn't need to, they will have had someone here and there'll be a dossier 250 pages thick."
O'Neill, who has been denied the services of senior men such as Jonny Evans, Gareth McAuley, Chris Brunt and Martin Paterson in South America, was quick to praise his own side's efforts.
Northern Ireland lie 78 places behind Uruguay in the FIFA rankings but exceeded expectations for much of the contest and even handed debuts to Luke McCullough, Paul Paton and Ryan McLaughlin.
"The most pleasing thing for me is the lads really seemed to enjoy the challenge," he said.
"I thought they were excellent and at times our possession of the ball was superb.
"Steven Davis was immense - as good a performance as he's had under me - and Sammy Clingan and Oliver Norwood too.
"The lads on debut were a credit as well and right through the team the application was first rate.
"It's an extremely young squad and we couldn't ask any more on the night against top-class opponents who are heading to the World Cup."