Opting to bat first, Jayawardene (42) added 63 runs with Tillakaratne Dilshan (35) but Sri Lanka could not capitalise on the strong start on a sluggish track and posted 139 for four wickets against the 2009 champions.
Jayawardene then returned to marshal his bowlers who restricted Pakistan to 123 for seven to earn a place in Sunday's final against either Australia or West Indies. Rangana Herath justified his return to the side claiming three for 25, including two off successive deliveries, while Ajantha Mendis (2-27) and Angelo Mathews (2-27) shared four wickets between them. Captain Mohammad Hafeez (42) top-scored for his team after being dropped twice, while Umar Akmal remained not out on 29 in a rematch of the 2009 final.
Pakistan responded well with Hafeez and Imran Nazir (20) adding 31 off the first six overs but once Mendis separated them by removing Nazir, their chase never got the momentum again. Angelo Mathews reduced Pakistan to 57 for three by removing Nasir Jamshed and Kamran Akmal in the same over before left-arm spinner Herath wrecked them.
Playing Herath ahead of teenager spinner Akila Dananjaya proved a master stroke as the 34-year-old spinner bowled out Shoaib Malik for six and then struck a double blow. He foxed Hafeez, who had stepped out to hit him, to present Kumar Sangakkara with an easy stumping and in his next delivery, bowled Shahid Afridi for a golden duck on the 16th anniversary of the batsman's fastest century that came off 36 balls.
Mendis further tightened the screw by removing Sohail Tanvir and Pakistan could score six of the 23 runs they required in the tidy last over sent down by Nuwan Kulasekara.
(Reporting by Shihar Aneez; Editing by Amlan Chakraborty)