Sri Lanka defeated Pakistan by five wickets in the last Super Four round match at the Dubai International Cricket Stadium, on Friday.
Sri Lanka chased down the 122-run target in 17 overs with five wickets to spare.
Pathum Nissanka remained unbeaten for 55 from 48 balls.
The two sides will meet again in the final on Sunday.
Earlier, an excellent bowling display by Sri Lanka bowlers bundled out Pakistan for just 121 runs.
Babar Azam top-scored with a 29-ball 30.
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Sri Lanka innings
That's it. Sri Lanks win by 5 wickets.
WICKET: Hasnain gets Shanaka on the very next ball. He departs for 21.
Sri Lanka - 113/5 in 16.3 overs.
SIX: Shanaka hits Hasnain for a six.
Sri Lanka - 107/4 in 16 overs.
Sri Lanka - 103/4 in 15 overs.
SIX: Shanaka hits Rauf for a six.
Sri Lanka - 92/4 in 14 overs.
50 up for Nissanka. Brilliant knock.
Sri Lanka - 87/4 in 13 overs
Sri Lanka - 84/4 in 12 overs.
Sri Lanka - 80/4 in 11.3 overs.
WICKET: Usman Qadir gets Rajapaksa. He goes for 24.
SIX: Nissanka hits Usman for a massive six.
Sri Lanka - 73/3 in 11 overs.
Sri Lanka - 68/3 in 10 overs.
SIX: Rajapaksa hits Usman for another six.
Sri Lanka - 57/3 in 9 overs
Sri Lanka - 53/3 in 8 overs.
SIX: Rajapaksa hits Usman Qadir for a six.
Sri Lanka - 45/3 in 7 overs.
Sri Lanka - 37/3 in 6 overs.
Sri Lanka - 29/3 in 5 overs.
WICKET: Rauf gets Dhananjaya. He departs for 9.
Sri Lanka - 22/2 in 4 overs.
WICKEt: Rauf gets Gunathilaka. He departs for a duck as well.
Sri Lanka 2/2 in 1.2 overs.
WICKEt: Hasnain removes Mendis. He departs for a duck.
Sri Lanka 0/1 in 0.2 overs.
Pakistan innings
WICKET: Madushan gets Haris for a duck. Pakistan bowled out for 121 in 19.1 overs.
Pakistan - 121/9 in 19 overs.
WICKET: Nawaz gets run out for 26.
SIX: Nawaz hits Madushanka for a six.
Pakistan - 110/8 in 18 overs.
WICKET: Theekshana gets Usman Qadir. He departs for 3.
SIX: Nawaz sends Theekshana to the stands.
WICKET: Theekashana removes Hasan Ali for a duck.
Pakistan 95/7 after 16.
WICKET: Hasaranga bowls Asif Ali for a duck.
WICKET: Hasaranga gets Iftikhar on the very next ball. He goes for 13.
SIX: Iftikhar hits Hasaranga for a six.
Pakistan - 91/4 in 15 overs.
Pakistan - 84/4 in 14 overs.
Mohammad Nawaz walks in.
WICKET: Dhananjaya removes Khushdil Shah. He walks back for 4.
Pakistan - 84/4 in 13.3 overs.
Pakistan - 81/3 in 13 overs.
Pakistan - 78/3 in 12 overs.
Pakistan - 74/3 in 11 overs.
Khushdil Shaha joins Iftikhar in the middle.
WICKET: Hasaranga removes Babar Azam. He departs for 30.
Pakistan - 68/3 in 10.4 overs.
Pakistan - 66/2 after 10 overs.
Iftikhar Ahmed walks in.
WICKET: Karunaratne removes Fakhar. He goes for 13.
Pakistan - 63/2 after 9.2 overs.
Sri Lanka put a squeeze on runs. Just two from the 9th. Pakistan 62/1.
Pakistan - 60/1 after 8 overs.
Pakistan - 53/1 after 7 overs.
Pakistan - 49/1 after 6 overs.
Pakistan - 37/1 after 5 overs.
Pakistan - 34/1 after 4 overs.
Fakhar Zaman walks in.
WICKET: Liyanagamage gets Rizwan. He departs for 14.
Pakistan - 28/1 after 3.3 overs.
Pakistan - 25/0 after 3 overs.
Pakistan - 19/0 after 2 overs.
Pakistan - 11/0 after 1 over.
The flags of all six participating nations and the United Arab Emirates flew at half-mast to mark the death of Queen Elizabeth II, who died Thursday.
Sri Lanka have made two changes from their previous win over India, who bowed out of the tournament with two losses in the Super Four, with Dhananjaya de Silva and debutant Pramod Madushan, added to the team.
"Been lucky with the toss, you never know what will happen," said Shanaka.
"But it's been our charm to bowl first. It's good we are playing Pakistan once before the final."
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Pakistan, who won a thriller against Afghanistan on Wednesday to book their final berth, have also made two changes.
"We would have also bowled first," said skipper Babar Azam.
"Two changes -- Shadab (Khan) and Naseem (Shah) are not playing, Usman Qadir and Hasan Ali are in."
Teams
Pakistan: Mohammad Rizwan (wk), Babar Azam (capt), Fakhar Zaman, Iftikhar Ahmed, Khushdil Shah, Asif Ali, Mohammad Nawaz, Usman Qadir, Haris Rauf, Mohammad Hasnain, Hasan Ali
Sri Lanka: Pathum Nissanka, Kusal Mendis (wk), Dhananjaya de Silva, Danushka Gunathilaka, Bhanuka Rajapaksa, Dasun Shanaka (capt), Wanindu Hasaranga, Chamika Karunaratne, Pramod Madushan, Maheesh Theekshana, Dilshan Madushanka
Umpires: Ahmed Shah Pakteen (AFG), Anil Chaudhary (IND)
TV Umpire: Masudur Rahman (BAN)
Match Referee: Andy Pycroft (ZIM)