Kumar Sangakkara, who remained unbeaten on 144 at the end of the fourth day in Colombo, has said Pakistan 'shifted the momentum their way' by taking late wickets.
The loss of Mahela Jayawardene forced Sri Lanka to go on the defensive, he said, allowing Pakistan to regain control.
Sri Lanka's main target on day five, he said, would be to play out a session and save the follow-on.
Sangakkara scored his 30th century, putting him ahead of Don Bradman in the list for the most centuries.
This, Sangakkara said, was a 'great honour'.
He now shares the 8th spot with Australia’s Matthew Hayden on the all time list of top century scorers in test cricket.
Meanwhile, Sri Lanka were on 367 runs for the loss of 5 wickets at lunch.