Ishtiaq fought back into the game from two frames down to register 4-2 victory over Mian Mohammad Shiraz the scores being 34-71, 47-66, 86-11, 64-15, 68-27, 70-37.
Ahsan also recovered after conceding the opener to post 48-53, 60-58, 50-28, 61-37, 56-42 victory over Qamar Zaman Khan in the all-Punjab battle.
Earlier in the morning, defending champion Asjad Iqbal suffered a severe blow when he was blanked 4-0 by Ahsan Javaid in the quarter-finals. The scores were 55-6, 55-41, 61-40, 45-26.
Last year's losing finalist Hamza Akbar was knocked out from the event the other day.
In the other three quarter-finals, Mohammad Shiraz struggled to beat Rizwan Hashmi 4-3; Ishtiaq inflicted 4-1 defeat on Ayaz Khan while Qamar Zaman overcame Yasir Rehman 4-2.
The best of nine frames final will be played on Thursday at 12.00noon. Both the finalist have already qualified to represent the country in the 11th Asian under-21 snooker championship slated in the Indian city of Indore from April 7 to 15.
Results
Quarter-finals Mian Mohammad Shiraz bt Rizwan Hashmi 4-3 (91-39, 21-64, 29-62, 68-64, 68-12, 39-55, 59-19; Mohammad Ishtiaq bt Ayaz Khan 4-1 (64-44, 51-40, 81-31, 39-65, 99-0); Qamar Zaman Khan bt Yasir Rehman 4-2 (61-51, 25-51, 67-27, 59-48, 52-62, 62-19); Mohammad Ahsan Javaid bt Asjad Iqbal 4-0 (55-6, 55-41, 61-40, 45-26).
Semi-finals Mohammad Ishtiaq bt Mian Mohammad Shiraz 4-2 (34-71, 47-66, 86-11, 64-15, 68-27, 70-37); Mohammad Ahsan Javaid bt Qamar Zaman Khan 4-1 (48-53, 60-58, 50-28, 61-37, 56-42).
