England batting coach Graham Gooch insists captain Alastair Cook will prove himself to be a top one-day batsman for his country.
The 26-year-old returned to the one-day scene in June after a 15-month absence.
"As he gains more experience, I have no reason to believe that Alastair won't be a very good and match-winning batsman," Gooch told BBC Essex.
"He wants to lead the side in his own image, to set the tone at the top of the order."
He added: "I was always convinced he would be a success because he was a success for Essex when he played one-day cricket."
But he recovered to register knocks of 119 and 95 on the way to a 3-2 series win over the tourists.
"A lot of people questioned his elevation to the position of captain against Sri Lanka," said former England batsman Gooch, who is also Cook's coach at Essex.
"They especially questioned his ability to change the way he plays, he plays a certain style in Test cricket, which has worked very well.
"But he managed to adapt to the one-day game and got a century and a 90 and I think was man of the series.
"He answered a few critics, but that's not why he continues to prove [he is worthy], Alastair's a smart lad.
"And when you're a fine player like he is, they find a way to score runs."
Cook will be rested against Ireland on Thursday, with Eoin Morgan taking the captaincy, but he will return for the upcoming ODI series with India.