Opener Abdullah Shafique's maiden double century and an unbeaten 132 by Agha Salman put Pakistan in the box seat Wednesday on day three of the second test against Sri Lanka.
The tourists reached 563-5 at stumps, leading Sri Lanka by 397 runs in their first innings at Colombo's Sinhalese Sports Club.
Salman and concussion substitute Mohammad Rizwan, on 37, were batting in an unbeaten stand of 95 after Shafique's departure on 201.
Salman played attacking cricket to reinforce Pakistan's new aggressive style in this series and reached his second test ton with a boundary.
Shafique led the mammoth reply in response to Sri Lanka's 166 as he put on three century stands including a 124-run sixth-wicket partnership with Salman.
Shafique, who began the day on 87, reached 200 in the final session with a single off Asitha Fernando, taking off his helmet and pointing to his name on the back of his jersey.
But he was soon caught out at deep mid-off by left-arm spinner Prabath Jayasuriya, who also had skipper Babar Azam for 39 earlier in the day.
Fernando cut short Saud Shakeel's knock on 57 in the afternoon session to take his wicket tally to three.
The fast bowler came around the wicket to trap the left-handed Shakeel lbw and end a 109-run partnership with Shafique.
Wicketkeeper-batsman Sarfaraz Ahmed made 14 before he retired hurt after feeling dizzy, likely due to a blow he received on his helmet on the first ball faced from Fernando.
He was finally substituted by Rizwan.
Shafique passed 150 for the second time against Sri Lanka with a single off Ramesh Mendis, and then went past his previous test best of 160 not out.
Pakistan resumed on 178-2 after Tuesday's downpours restricted the action to just 10 overs.
Shafique started cautiously but soon hit two successive boundaries off Fernando before a single got his hundred.
Azam added 11 to his overnight 28 before being trapped lbw, with the decision upheld by the third umpire after review.
It was the sixth time Azam had been dismissed in test cricket by Jayasuriya, who bowled unchanged from one end in the first session.
Pakistan won the first test in the two-match series by four wickets.
PAKISTAN: Abdullah Shafique, Imam-ul-Haq, Shan Masood, Babar Azam (captain), Shaud Shakeel, Sarfaraz Ahmed (wk), Agha Salman, Noman Ali, Shaheen Shah Afridi, Naseem Shah, Abrar Ahmed.
SRI LANKA: Dimuth Karunaratne (capt), Nishan Madushka, Kusal Mendis, Angelo Mathews, Dhananjaya de Silva, Dinesh Chandimal, Sadeera Samarawickrama (wk), Ramesh Mendis, Prabath Jayasuriya, Asitha Fernando, Dilshan Madushanka.