The ICC Champions Trophy semi-final line-up will be decided as Sri Lanka and Pakistan conclude the group stage with a winner-take -all meeting in Cardiff.
Both sides come into the match on the back of inspirational victories.
Pakistan began their tournament with a heavy defeat at the hands of rivals India, but responded with a fine win over South Africa.
Sri Lanka on the other hand, were second best to the Proteas before pulling off the highest successful chase (322) in The Oval's ODI history against Virat Kohli's men.
Kusal Mendis (89) and Danushka Gunathilaka (76) set things up before Angelo Mathews' captain's knock of 52 not out saw them home.
Gunathilaka is only in the squad as a replacement for the injured Chamara Kapugedera, while Kusal Perera had to pull out of the tournament this week after tearing his hamstring during that India game - Dhananjaya de Silva has been called up.
There were further fears before the game as Thisara Perera was hit on the head during training, but he is expected to be fit to play on Monday.
-- Sri Lanka Cricket (@OfficialSLC) June 11, 2017
BREAKING: @PereraThisara who was under medical observation after a fluke ball hit him in the head declared medically fit for tomorrows game-- Sri Lanka Cricket (@OfficialSLC) June 11, 2017
Unbeaten tournament favourites England await the winner in the final four back at Sophia Gardens on Wednesday.
With Upul Tharanga still banned for a slow over-rate infraction, Dhananjaya is likely to come straight into the side. Unlike Gunathilaka, who was training with the squad, Dhananjaya is lacking match sharpness and his ability to get up to speed could be crucial.
All-rounder Mohammad Hafeez has impressed with his remodelled action in this tournament. The veteran also needs to set the tone for Pakistan in the field. Sri Lanka have suffered four run outs in two games and Pakistan must be sharper across the field than they have been so far.
Sri Lanka: Niroshan Dickwella, Danushka Gunathilaka, Kusal Mendis, Dhananjaya De Silva, Angelo Mathews, Asela Gunaratne, Dinesh Chandimal, Thisara Perera, Suranga Lakmal, Lasith Malinga, Nuwan Pradeep.
Pakistan: Azhar Ali, Fakhar Zaman, Babar Azam, Mohammad Hafeez, Shoaib Malik, Sarfraz Ahmed, Imad Wasim, Mohammad Amir, Shadab Khan, Hasan Ali, Junaid Khan.
LAST ODI MEETING:
Almost two years have passed since the last game between these sides. Sri Lanka registered a dominant 165-run win in Hambantota, with Kusal Perera scoring 116, although Pakistan already had the five-match series wrapped up before the hosts made it 3-2 in this concluder.
Hafeez revels in Pakistan's standing as perennial dark horses: "We're always unpredictable. We have the talent, but still you never know when it comes. At the same time, being consistent is something we always work on."
"We've got a young set of players who are still coming through the ranks and who are still unfamiliar with the international level, but the skill is obviously there. We know what we can do. We showed the other day." - Mathews backs Sri Lanka's inexperienced side to fire again.
- Pakistan hold the upper hand in Champions Trophy encounters with Sri Lanka (W2, L1); they secured a four-wicket win last time out in 2006.
- Shoaib Malik is set to make his 250th ODI appearance in this match; he'll be the 10th man to record that many for Pakistan.
- In fact, Shoaib Malik is in line to make his 18th appearance in the Champions Trophy; only four players have featured in more games in the competition (Mahela Jayawardene, Kumar Sangakkara, Sanath Jayasuriya and Rahul Dravid).
- Kusal Mendis needs 55 to reach 1,000 ODI runs; he comes into this game on the back of posting 89 in Sri Lanka's last game.