Top seed Aamir Atlas Khan, the Pakistan number one, crashed out of the PSF-AVT Khyber Pakistan International Circuit No4 after losing to unseeded compatriot Farhan Mehboob in today's quarter-finals of the PSA World Tour Challenger 10 event at the Mushaf Squash Complex in Islamabad.

Mehboob (pictured), a 24-year-old from Peshawar, defeated Khan - more than 100 places higher in the world rankings - 14-12, 11-7, 12-10 in 58 minutes to earn an unexpected semi-final clash with fourth-seeded fellow countryman Nasir Iqbal.

Teenager Iqbal, also from Peshawar, despatched Pakistani Waqas Mehboob 11-9, 15-13, 12-10.

There was positive news for Aamir's younger brother Danish Atlas Khan in the other half of the draw. The unseeded 18-year-old ousted New Zealand's No3 seed Kashif Shuja 12-10, 11-3, 11-9 to claim a place in the other semi-final.

His opponent will be Yasir Ali Butt after the second seed scored the swiftest win of the day, beating Muhammad Saqib Yousaf 11-8, 11-8, 11-9 in 37 minutes.

Semi-final line-up:
Farhan Mehboob (PAK) v [4] Nasir Iqbal (PAK)
[2] Yasir Ali Butt (PAK) v Danish Atlas Khan (PAK)

Quarter-finals:
Farhan Mehboob (PAK) bt [1] Aamir Atlas Khan (PAK) 14-12, 11-7, 12-10 (58m)
[4] Nasir Iqbal (PAK) bt Waqas Mehboob (PAK) 11-9, 15-13, 12-10 (46m)
Danish Atlas Khan (PAK) bt [3] Kashif Shuja (NZL) 12-10, 11-3, 11-9 (41m)
[2] Yasir Ali Butt (PAK) bt Muhammad Saqib Yousaf (PAK) 11-8, 11-8, 11-9 (37m)

1st round:
[1] Aamir Atlas Khan (PAK) bt Mansoor Zaman (PAK) 11-7, 11-2, 11-5 (33m)
Farhan Mehboob (PAK) bt Syed Ali Shah Bokhari (PAK) 11-4, 11-7, 11-4 (31m)
Waqas Mehboob (PAK) bt [Q] Sadam Ul Haq (PAK) 11-4, 11-8, 11-8 (28m)
[4] Nasir Iqbal (PAK) bt [Q] Tayyab Aslam (PAK) 11-8, 11-6, 9-11, 11-13, 11-7 (75m)
[3] Kashif Shuja (NZL) bt Khawaja Adil Maqbool (PAK) 10-12, 11-9, 11-3, 3-11, 11-7 (50m)
Danish Atlas Khan (PAK) bt Aqib Hanif (PAK) 11-6, 13-11, 11-9 (38m)
Muhammad Saqib Yousaf (PAK) bt [Q] Asim Khan (PAK) 11-7, 11-8, 11-7 (37m)
[2] Yasir Ali Butt (PAK) bt [Q] Amaad Fareed (PAK) 14-12, 11-5, 6-11, 4-11, 11-6 (50m)

Qualifying finals:
Sadam Ul Haq (PAK) bt Syed Hamzah Shah Bukhari (PAK) 11-9, 11-8, 11-8
Amaad Fareed (PAK) bt Ahmad Amin (PAK) 11-6, 11-7, 11-2
Tayyab Aslam (PAK) bt Owais Khan (PAK) 11-5, 11-4, 11-7
Asim Khan (PAK) bt Mohammad Naeem (PAK) 11-8, 11-9, 9-11, 11-5

1st qualifying round:
Syed Hamzah Shah Bukhari (PAK) bt Suleman Khan (PAK) 11-5, 11-7, 11-4
Sadam Ul Haq (PAK) bt Muhammad Shoaib Hassan (PAK) 6-11, 11-6, 11-8, 8-11, 11-9
Ahmad Amin (PAK) bt Muhammad Shah Nawaz (PAK) 11-6, 9-11, 11-3, 11-9
Amaad Fareed (PAK) bt Israr Ahmed (PAK) 11-4, 11-8, 12-10
Tayyab Aslam (PAK) bt Zahir Shah (PAK) 12-10, 11-5, 12-10
Owais Khan (PAK) bt Nosherwan Khan (PAK) 6-11, 11-9, 12-10, 11-9
Mohammad Naeem (PAK) bt Ismail Rauf (PAK) 11-3, 11-3, 11-5
Asim Khan (PAK) bt Kashif Khan (PAK) 4-11, 11-7, 9-11, 11-2, 11-9