Sri Lanka 70-1 in reply to Pakistan's 551-6
Tillakaratne Dilshan was unbeaten on 46 and Kumar Sangakkara was on 22, the pair having added 59 runs for the second wicket at the Sinhalese Sports Club.
Pakistan had earlier declared their first innings at 551-6 an hour after the start of play.
Just 27 overs of the stipulated 90 were bowled during the day as rain washed out play in the last two sessions. The second day had also seen only 44 overs sent down.
Sri Lanka lead the three-match series 1-0, having won the first Test in Galle by 209 runs.
The third Test will be played in Pallekele from July 8.