Egyptian teenager Marwan El Shorbagy became the only unseeded player to reach the quarter-finals of the inaugural Egyptian People Tournament after beating compatriot Karim Ali Fathi in the second round of the PSA World Tour Challenger 10 squash event at the Heliopolis Club in Cairo.
Fathi, a qualifier, made his breakthrough in the opening round where he knocked out second seed Omar Abdel Aziz.
And the 18-year-old from Cairo took the opening two games against El Shorbagy, also 18, but ranked more than 130 places higher in the world rankings.
But El Shorbagy, the recently-crowned world junior champion, dug deep and - taking advantage of a hamstring injury sustained by Fathi early in the third game - took control of the match to draw level before claiming victory in an 8-11, 3-11, 11-4, 11-7, 11-8 scoreline.
El Shorbagy will now face third seed Ali Farag following the 19-year-old from Cairo's 11-3, 12-10, 11-8 win over fellow countryman Omar Abdel Meguid.
The other semi will also be an all-Egyptian affair, between top seed Karim Abdel Gawad and Andrew Wagih Shoukry, the No4 seed.
Gawad, the Alexandria-born world No38, recovered from a game to beat Ali Farag's older brother Wael Farag 11-13, 11-7, 11-9, 11-5, while Shoukry despatched Mazen Gamal 11-6, 12-10, 11-7.
RESULTS: PSA Challenger 10 Egyptian People Tournament, Cairo, Egypt
Quarter-finals:
[1] Karim Abdel Gawad (EGY) bt Wael Farag (EGY) 11-13, 11-7, 11-9, 11-5
[4] Andrew Wagih Shoukry (EGY) bt Mazen Gamal (EGY) 11-6, 12-10, 11-7
[3] Ali Farag (EGY) bt Omar Abdel Meguid (EGY) 11-3, 12-10, 11-8
Marwan El Shorbagy (EGY) bt [Q] Karim Ali Fathi (EGY) 8-11, 3-11, 11-4, 11-7, 11-8
Semi-final line-up:
[1] Karim Abdel Gawad (EGY) v [4] Andrew Wagih Shoukry (EGY)
Marwan El Shorbagy (EGY) v [3] Ali Farag (EGY)