Ravi Bopara insists Alastair Cook will successfully fight his England corner to keep the critics at bay en route to this winter's World Cup.

Cook could hardly have been surprised on Saturday when, after Sri Lanka had inflicted England's seventh defeat in eight one-day internationals, Kevin Pietersen and Michael Vaughan were on his case again.

It is equally predictable, of course, to hear support coming from within - and of all the team-mates Cook can count on, his near lifelong colleague Bopara tops the list.

There was nonetheless much apparent sincerity and zero equivocation in Bopara's voice as he stood up for the man he has seen prove doubters wrong so often.

In fact, Bopara - who has played alongside Cook for Essex and England for much of the past decade and has known him even longer - believes his captain is stronger for the adversity which has beset him for the majority of the past 12 months.

"I think what's happened to him over the past year has definitely made him stronger," said Bopara, unspoken reference not just to a potential sixth ODI series defeat under Cook's captaincy looming here but also the debacle of last winter's Ashes whitewash.

Bopara believes Cook has learned to live under the microscope as England captain in a time of much transition.

"He smiles a lot more now than he ever did ... he's handling it well," Bopara said.

"He knows what's coming and what to expect a little bit more.

"He deals with it better ... he'll come out the other side."

Resourcefulness and resilience are two traits which have so often served Cook well.

Bopara added: "He's trying his best to do the country proud, the fans proud, himself, his team-mates, his family.

"He's a good enough player to turn it around ... he's a fighter.

"I've seen him do it before."

Cook's own form, as well as his team's, has become a major issue - with no ODI century in 41 innings stretching back more than two years.

The 29-year-old has not flinched in a succession of crisis points - of which the latest is, by no means, the least.

Bopara, however, suggests it is no help to England to dwell on Cook alone - his sub-80 strike rate and the potential of others is a favourite theme for many - when the whole team needs to shape up.

"In the English culture, we're quick to jump on something that hasn't gone right," he said.

"One thing we must remember, it's not just Alastair Cook who hasn't scored over the past few games. There's been a lot of us.

"One man doesn't lose you a game, just as one man doesn't win you a game."

In England's latest defeat, by eight wickets to go 2-0 down with five to play after being bowled out for 185, Bopara cites a costly collective lack of nous.

"The second game was the one that was really disappointing," he said of a fixture in which he hit his second successive half-century.

"We didn't adapt to the change on the pitch.

"We played on the same pitch [as in Wednesday's first defeat], but it didn't play the same way.

"It was a lot slower and it turned a little bit more, and we went out with the mentality that we had to get 300 - when really 250, 260 would have been a good score.

"We didn't adapt quickly enough to the pitch and lost early wickets - you're losing the game if you do that."

Bopara himself has responded impressively to being left out of last summer's series against India, which England lost 3-1.

"Getting dropped against India was a shock - I remember the phone call quite clearly," he said.

"I didn't really want to tell anyone ... I was a little bit embarrassed.

"But a week later you get over it, and you work out your plan about getting back in."

Bopara has 110 ODI caps, yet has rarely been sure of his place for long.

"I get dropped a lot, actually," he said.

"I come back saying I'm more determined, I'm working harder - which is the truth.

"But I think I come back wiser every time ... more independent as a player.

"I think that is the key at this level - you've got to be very independent and not be so coach-driven.

"You've got to find it within yourself, and do it your way.

"I choose the way I go out and play and how I approach my innings - because I know that's best for me.

"I've played enough cricket to know."

Cook is unlikely to leave England's tour to attend Phillip Hughes' funeral in New South Wales, following the Australia Test batsman's death from injuries sustained when he was hit by a bouncer.

It is thought England will instead be formally represented at Hughes' state memorial service - on a date yet to be announced.