Niroshan Dickwella, Dinesh Chandimal dig deep to help Sri Lanka draw opening Test.
Mushfiqur Rahim makes history as Test hangs in balance.
Top knocks from Tamim Iqbal (133*), Liton Das (54*) and Mushfiqur Rahim (53*) helped Bangladesh end Day 3 on 318/3.
Tamim and Mahmudul start strongly after Mathews 199 drags Sri Lanka to 397.
Sri Lanka post 258/4 on opening day, Kusal Mendis made 54.
Karunaratne scored a splendid century in the second innings.
