"The fact that we are coming as underdogs releases the pressure. Yes, we didn't do well in the Asia Cup but we're getting better day by day. I'm confident of my team's progress," Mathews said on the eve of their Super 10 opener against Afghanistan.
Mathews said that his team needed just one win to get the momentum back.
"We're not looking too far ahead at the moment and we will take one game at a time. We need one good game to get our momentum back," said the skipper.
Afghanistan almost pulled off an upset during the 2015 World Cup in Australia when they threatened to chase down 237 before being bowled out for 232 in 49.4 overs and Mathews said Afghans were no more the minnows.
"We can't call Afghanistan minnows. They beat all the teams in the qualifiers and progressed. We are taking them very seriously. They can upset any team. We have to really play well to beat Afghanistan. They're really tough.
"It (2015 WC) was too close game. They really fought hard against us. We have to fight well. If we play to our potential, we can beat them," said Mathews.
With Lasith Malinga having stepped down as Sri Lanka captain, citing injury concerns at the last minute, Mathews was quoted as saying in media that he was not 'mentally prepared'. However, the Lankan all-rounder clarified his comments saying: "I think I used a wrong word 'not ready'
What I meant was I was not expecting the captaincy.
"I've been a part and parcel of the team and captain of the ODI and Test teams for about three years. I'm very familiar with the players. It's not a burden at all. My task now is to get the maximum out of players from the bunch that we have. I'm really confident."
The retirement of Mahela Jayawardene and Kumar Sangakkara have been a big blow to Sri Lanka as they've won only four of their 14 matches since beating India in Mirpur in 2014.
But Mathews said cricket has to live on and he urged the players to take up more responsibility and live up to the challenge.
"It's quite hard to fill those gaps. They served us for so many years. They've retired. Cricket will live forever...no one is permanent in the team. Whosoever comes into the team has to take responsibility. Yes, I've had a lean patch but I have been batting well at the nets and have to carry on," Mathews insisted.
Image: Sri Lanka captain Angelo Mathews.
Photograph: Reuters
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