Sri Lanka spinner Muttiah Muralitharan is still having treatment on a knee injury and will miss the second test against Pakistan starting tomorrow (Sunday). The 37-year-old, who has injured his patella tendon, is also a doubt for the third test.Wicketkeeper Prasanna Jayawardene returned to full training this week, but was also not considered for selection as Sri Lanka, who lead the three-match series 1-0 after a 50-run victory in Galle, named an unchanged squad.The only selection dilemma is the form of opener Malinda Warnapura, who has scored just 12 runs in his last four innings. Sri Lanka skipper Kumar Sangakkara called for improvement from his batsmen.Pakistan captain Younis Khan put the first test defeat down to the pressure on his young players as the team collapsed from 71 for two to 117 all out in the second innings.We have youngsters in the team and I think they will learn from their mistakes, he said.If we play to our potential in the next two tests we may square the series or win it.Former skipper Shoaib Malik, who bats at number six, could find his place under scrutiny. He last scored a century in March 2006.Young all-rounder Fawad Alam, 23, could be a possible replacement after an impressive 83 not out in a warm-up game before the Galle Test.