The start was delayed by 30 minutes due to a wet outfield caused by overnight rain.
Bad weather has been forecast on all five days of the Test.
Both teams went in with two spinners -- Saeed Ajmal and Abdur Rehman for Pakistan, and Rangana Herath and Dilruwan Perera for the hosts -- on a grassless pitch expected to take turn later in the match.
The two-Test series is the final one for former Sri Lankan captain Mahela Jayawardene, who will retire from the longer format after the second Test in Colombo next week.
Sri Lanka: Angelo Mathews (capt), Kaushal Silva, Upul Tharanga, Kumar Sangakkara, Mahela Jayawardene, Kithuruwan Vithanage, Niroshan Dickwella, Rangana Herath, Dilruwan Perera, Shaminda Eranga, Dhammika Prasad.
Pakistan: Misbah-ul Haq (capt), Ahmed Shehzad, Khurram Manzoor, Azhar Ali, Younis Khan, Asad Shafiq, Sarfraz Ahmed, Saeed Ajmal, Abdur Rehman, Mohammad Talha, Junaid Khan.
Umpires: Ian Gould (ENG) and Bruce Oxenford (AUS)
TV umpire: Richard Illingworth (ENG)