Karunaratne and Tharanga batted cautiously conceding four consecutive maidens to Mustafixur Rahman at one stage .
Karunaratne was dropped by Shakib Al Hasan of fellow spinner Mehedi Hasan on seven .
Karunaratne , who was dropped by Shakib Al Hasan of fellow spinner Mehedi Hasan on seven , and Tharanga batted cautiously conceding four consecutive maidens to Mustafixur Rahman at one stage .