Teenaged fast bowler Mohammad Aamer ripped through Sri Lanka's middle-order to leave Pakistan in control of the first cricket Test in Galle on Monday.
The 17-year-old left-armer, playing his first Test match, grabbed three wickets for two runs as Sri Lanka collapsed from their lunch score of 70-2 to 101-5 soon after resumption.
The hosts went to tea on the third day struggling at 182-7 in their second innings, an overall lead of 132 runs with three wickets in hand at the Galle International Stadium.
Angelo Mathews was unbeaten on 24 and Nuwan Kulasekera was on nine.
Aamer, who hero-worships Pakistan's left-arm pace legend Wasim Akram, followed his three wickets in the first innings with a hostile burst soon after lunch.
He had Tharanga Paranavitana, Mahela Jayawardene and skipper Kumar Sangakkara caught by wicket-keeper Kamran Akmal in the space of 16 deliveries on a lively wicket freshened up by early morning rain. Paranavitana, top scorer in Sri Lanka's first innings with 72, once again held the innings together with 49, but found little support from the top order.
Jayawardene failed to score and Sangakkara, leading Sri Lanka for the first time in a Test series, made nine and 14 in the two innings. Sri Lanka were just 51 runs ahead with half the side back in the pavilion when Thilan Samaraweera and Tillakaratne Dilshan put on 37 for the sixth wicket.
Dilshan looked set while making 22 when he fell to Pakistan captain Younus Khan's part-time seam bowling, edging a catch to Khurram Manzoor in the slips. Samaraweera was dismissed soon after for 34, beaten by the flight and turn from off-spinner Saeed Ajmal to give Misbah-ul Haq a low catch in the slips.
Rangana Herath, who opened the innings late Sunday as a nightwatchman and played out the lone over from Aamer, batted for an hour and 28 minutes to make 15. When play started 30 minutes late due to a wet outfield, Pakistan earned a break off the second ball when Malinda Warnapura edged Umar Gul to a diving Younus at second slip before a run had been scored.
Left-handed Paranavitana and Herath defied the Pakistani seamers to put on 68 for the second wicket before the nightwatchman was trapped leg-before-wicket by Younus just before lunch. The three-match series is the first between the two nations since gunmen attacked the Sri Lankan team bus in the Pakistani city of Lahore on March 3 while the squad was en route to resume a Test match.
The attack left seven Sri Lankan players injured and eight Pakistani security forces dead. The two teams recently contested the World Twenty20 final in England, in which Pakistan beat Sri Lanka by eight wickets.