Chasing a modest 237 to win, opener Fakhar Zaman (50) cracked a 36-ball 50 at the top but Pakistan suffered an inexplicable collapse to slip to 162 for 7.
After making into semi-finals in style, confident Pakistani skipper Sarfraz Ahmed said that his side is ready to take on England in the first semi-final of the ICC Champions Trophy 2017 cricket tournament.
Considering that they are up against a side that is miles ahead of Sri Lanka in terms of both quality and form, Sarfraz said playing positive cricket will hold the key.
Ahmed, who had already survived two near run-outs, received more let-offs when he was dropped on 38 by Thisara Perera, who had the ball at chest height, and on 40 by Seekkuge Prasanna, who couldn't hold on to a diving catch.
"I really hope that Malik and Hafeez come good in the semi-final since the team would be pinning its hopes on them, especially against a top-class England unit, which unlike Sri Lanka, is not expected to give Pakistan chances of coming back in the game". Fittingly, Sarfraz hit the winnings runs, guiding Malinga to the third man boundary.
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The first, issued on 27 January, led to chaos and protests at airports and in various cities before it was blocked by the courts. The state says the policy is unconstitutional because it shows anti-Muslim bias.
Pakistan, meanwhile, were fined for a slow over-rate after they were ruled to be one over short of the target when time allowances were taken into consideration.
Pakistan made the Sri Lankans bat first, and dismissed them for 236 in 49.2 overs. The skipper finished with an unbeaten 61.
That platform would be destroyed with disdain over the next four overs as Pakistan unleashed its two left-arm pacers in tandem.
Sri Lanka, despite a battling 73 by opener Niroshan Dickwella, were bowled out for what appeared an under-par total, with Junaid Khan and Hasan Ali each taking three wickets as headline acts of Pakistan's pinpoint seam attack. Junaid Khan (3-40) and Hasan Ali (3-43) had better figures than Amir (2-53) but it was the left-armer's twin strike that squeezed the life out of Sri Lanka's innings. Hasan Ali's brilliance with the ball, finding annul swing where most other bowlers in the tournament have been unable to, galvanized Pakistan and Junaid Khan's left-arm swing proved a hard proposition with the new ball too. The risky Dickwella departed for 73 as the middle-order collapsed at the feet of Amir and Junaid, leaving Sri Lanka now struggling at 167-7.
In the next over, Sarfraz took a brilliant catch diving to his right to dismiss the risky Dickwella off Amir's bowling. The trio found enough movement off the pitch as well as in the air to make life tough for the Sri Lankan middle and lower order.
Pakistan needed 75 to win from 120 balls at that stage and from there on, it was a case of Sarfraz and Amir's persistence as much as it was of Sri Lanka's sloppiness.