Colombo: Who best can break the web of spin will determine the winner between host Sri Lanka and 2009 champion Pakistan in a World Twenty20 semi-final at the R Premadasa Stadium on Thursday. Ajantha Mendis and teenage sensation Akila Dananjaya lead Sri Lanka's hopes when they appear in the capital, Colombo, for the first time in the tournament. Pakistan will be relying heavily on mystery spinner Saeed Ajmal and slow left-armer Raza Hasan to counter the formidable Sri Lanka batsmen. Sri Lanka knocked out defending champion England to reach the semi-finals, and for a chance to avenge its 2009 final defeat. Pakistan is appearing in a record fourth successive semi-final having edged out archrival and 2007 champion India on a better net run-rate. Sri Lanka last played a Twenty20 in Colombo three years ago. It played its group matches in Hambantota and Super Eights games in Pallekele for four wins and a loss. "We don't have to cast our mind back so long," captain Mahela Jayawardene said. "Our mind will be what we've done over the last two weeks ... how we are going to approach the semi-finals." Mendis and Dananjaya have combined for 13 wickets in the tournament and pace bowler Lasith Malinga also was in form after destroying England with a five-wicket haul on Monday. And with seamers Nuwan Kulasekera, Thisara Perera and Angelo Mathews, Sri Lanka looks to have their bowling bases covered against Pakistan, which easily beat them in the 2009 final at Lord's. Sri Lanka's top three seasoned batsmen, Jayawardene (168 runs), Tillakaratne Dilshan (144) and Kumar Sangakkara (130), have scored consistently in the tournament. They are also comfortable against spinners. Jayawardene said batsmen have started to pick Ajmal and Mendis well, and toned down the focus on the two spinners. "Those guys have been playing for almost, I don't know, five-six years now, so I don't know whether there's enough mystery in it," he said. "I don't call them mystery spinners, people have analyzed them and have seen videos of them, but all these guys are good quality spinners." Pakistan had a bumpier road to the semi-finals. It scraped past South Africa in the Super Eights then was crushed by India. But captain Mohammad Hafeez outwitted Australia by bowling five spinners for the first 17 overs. Pakistan won by 32 runs and backed into the semis on a better net run-rate than India. "We are really blessed with some very good spinners in the world like Saeed Ajmal, Shahid (Afridi) and newcomer Raza Hasan (who) is showing a great talent," Hafeez said. Pakistan spinners have taken 18 wickets â double what the seamers have pocketed. The opening pair of Imran Nazir (133 runs) and Hafeez (122) have been solid, and No. 3 batsman Nasir Jamshed (144) has scored two half-centuries, including a vital 55 against Australia on Tuesday. Sri Lanka and Pakistan are very familiar with each other, and neither expect to be surprised. "We believe as a team we can beat them," Hafeez said. When asked if he was planning to deploy all five of his spinners against Sri Lanka, Hafeez smiled. "T20 is all about giving surprises ... most of the time we are getting success in that," he said. "I have no idea what it will be tomorrow, but you will know it."