The 28-year-old's unbeaten 97 spanned over 325 minutes and 230 balls, enabling Sri Lanka to recover from three for nine after they decided to bat first.

Pakistan fast bowlers Shoaib Akhtar and Mohammad Sami took three wickets apiece.

Batting with a runner and in pain due to acute cramp in the final session, Samaraweera shared in three significant partnerships.

He was closing on his fourth Test hundred in his 23rd Test when the umpires offered the batsmen the chance to come off for bad light with five overs remaining in the day.

The tall right-hander from Colombo added 68 runs in 168 balls with Sanath Jayasuriya (38), 55 with Jehan Mubarak (34) and an unbroken 53 with Rangana Herath (28).

Jayasuriya, in his 93rd Test, also became the second Sri Lankan after Aravinda de Silva to score 6,000 runs.

Sri Lanka were soon in trouble in the first Test match between the countries since March 2002.

Getting plenty of bounce and some movement, Shoaib and Sami rocked them with the wickets of Marvan Atapattu (0), Kumar Sangakkara (2) and Mahela Jayawardene (0) in the first four overs.

Shoaib removed Atapattu lbw and had Sangakkara caught by Imran Farhat at third slip, while Sami got Jayawardene to nibble at a ball in his second over.

Samaraweera, who scored a hundred on his Test debut against India in 2001, looked confident from the start, however, as he notched up his highest score outside Sri Lanka.

He and Jayasuriya, who was twice dropped off the bowling of Abdul Razzaq, took the score to 58 at lunch.

Jayasuriya was out soon after reaching 6,000 Test runs, hitting a drive straight to Asim Kamal in the covers off Sami.

Sri Lanka had progressed to 142 for four at tea with Samaraweera getting good support from Mubarak, who edged Sami to Inzamam at first slip soon after the interval.

Leg spinner Danish Kaneria then held a return catch from Romesh Kaluwitharana (4) to leave Sri Lanka in trouble again on 147 for six.

Shoaib returned to force Chaminda Vaas to miscue a pull shot to Yousuf Youhana at mid-on after a cameo innings of 22 from 28 balls including five fours.