Pakistan, sent in to bat in overcast conditions by Sri Lankan captain Kumar Sangakkara, collapsed to 34-2 within the first hour as left-arm seamer Thilan Thushara grabbed two wickets in four balls.
Manzoor (93) and Yousuf (90) lifted the beleaguered tourists with a 167-run partnership for the third wicket as Pakistan moved to 289-7 by stumps at the Sinhalese sports club here.
Manzoor, a 23-year-old from Karachi, fell short of his maiden Test century in only his fifth match, while the seasoned Yousuf missed his 25th ton after the pair had stayed together for more than a session.
Shoaib Malik (45) and Misbah-ul Haq (27) put on 75 for the fifth wicket to carry the total to 285-4 before the second new ball taken shortly before stumps claimed three wickets for two runs.
Thushara trapped Malik leg-before for his third wicket of the day, before Nuwan Kulasekera had Misbah caught behind and bowled Umar Gul to open up the Pakistan tail.
Pakistan are hoping to deny Sri Lanka a clea