Moeen Ali believes victory over Sri Lanka will be a massive boost to England's confidence for the remainder of the 2015 World Cup.
The Worcestershire all-rounder and his team-mates will face the Sri Lankans in Wellington on Saturday evening.
Moeen hit his second ODI hundred in the win over Scotland in Christchurch as England achieved their first success after defeats at the hands of Australia and New Zealand.
Victory against the Sri Lankans and then Bangladesh would seal a last eight spot ahead of the final Pool A meeting with Afghanistan.
Moeen said: "We are going out to win the next two. That's a very important game against Sri Lanka.
"If we can win that it will give the team a lot more confidence of being a very good one-day side and a major side in the competition."
But Sri Lanka will provide a stiff test after defeating England 5-2 in an ODI series in November and December.
Moeen, who scored his first ODI ton in the first match of that series in Colombo, said: "Obviously we lost to them in Sri Lanka. We know a lot about them now having played against them quite a bit last year.
"They have some really good batters and that will be the key, their four main batters, Dilshan, Sangakkara, Mahela and Mathews.
"We saw the other day Mahela is in good form so we are going to have to bowl really well and obviously bat well against them.
"It will be a close game, a tight game so we will have to be at our best to beat them."
Moeen admits a chat with England assistant coach Paul Farbrace enabled him to banish any negative thoughts and he responded with his 128 from 107 balls against the Scots.
He said: "You can't listen to everyone. After the first two games, people had been talking negatively. "I tried to erase that and concentrate on being positive. I try to speak to my parents, my brother. Paul Farbrace is really good at that.
"I had a good chat with Paul Farbrace before the game and he took away everything negative and just told me to be true to myself and play the way I wanted to play.
"He said it didn't matter how many I scored as long as I played with freedom.
"The innings against Scotland was the first time I didn't pre-meditate in this World Cup. I just reacted to balls and enjoyed it. "
Moeen also tries to switch off from cricket when time allows.
He said: "I take my mind away from cricket a little. Sometimes you think about cricket so much, it can take over."
