Kusal Mendis has earned his place - Mathews

Little more than a week after moving Lahiru Thirimanne to no. 3 in the hope he will end his lean trot, Sri Lanka seem set to replace him in the side with 20-year-old Kusal Mendis. Thirimanne's contribution to Sri Lanka's 484 in Galle was 16 from 62 balls, and captain Angelo Mathews suggested that both Thirimanne and the team could benefit from his exclusion from the XI for the second Test.

Thirimanne has been a consistent top-order batsman in ODIs, but has not reproduced that form in Tests, where he averages 24.84 after 45 innings. His form in 2015's home season has been particularly worrying. In seven Tests since June, Thirimanne has hit 248 runs at an average of 20.66.

With Kusal Perera playing his third Test, and Milinda Siriwardene playing his second, Mendis' likely inclusion does leave Sri Lanka's top order light on experience. Mathews said Sri Lanka had little choice but to take the risk.

"We're looking at Kusal Mendis tomorrow for no. 3, so if he plays it will be a straight swap," Mathews said. "We are in a position where we have to make changes. Sometimes a change is refreshing on those players failing quite a lot in the recent past. When you hit a rough patch you need a break. They are good players. They will always come back hard. I am pretty sure that Thirimanne will bounce back really hard. At the moment we haven't got any choices we just have to make that call. We had lots of debate about it, but sometimes you just have to give things a go."

Mendis, a recipient of the Schoolboy Cricketer of the Year award, and last year's Sri Lanka under-19 captain is largely untested, in senior cricket. He was picked in the squad on potential, after he hit 255 runs from three innings in the Moin-ud-Dowlah three-day tournament in Hyderabad, in September.

"Kusal Mendis has earned his place and hopefully he'll grab his opportunity," Mathews said. "We can't put a lot of pressure on him and we can't expect him to do wonders. There will be nervous times for him but we're there to help him out as a team and as a captain. He's got the talent. We're hopeful that he'll come out good."

Sri Lanka are also set to retain Kusal Perera as wicketkeeper batsman. He has been impressive with the bat so far, with two fifties from three Test innings, but has not been as convincing behind the stumps. However, Mathews suggested his role would not change in the short-term, particularly as Perera's keeping wickets allows Dinesh Chandimal to move to no. 4.

"Kusal Perera is the ideal no. 7 for us because his game is more suited to that position. He plays a lot of shots and we need someone who can bat with the tailenders and go for big shots. Kusal Perera plays his normal game any given time, whether it's a T20 or ODI or Test. We don't want him to change. We are trying to slot him in a position where he bats normally."

Mathews said Rangana Herath would take over the vice-captaincy role if Thirimanne is dropped for the second Test.