English qualifier Olivier Pett continued his giant-killing run in the Santiago Open in Spain when he upset second seed Stephen Coppinger to reach the semi-finals of the PSA World Tour International 25 event at Shopping Center Area Central in Santiago de Compostela.
It was 24 hours earlier - on his 23rd birthday - that Pett made his breakthrough by beating higher-ranked fellow countryman Adrian Waller to secure a surprise place in the quarter-finals
But the world No87 from Sussex secured one of the biggest scalps of his career when he recovered from a game down to beat South African number one Coppinger, ranked more than 50 places higher, 8-11, 11-4, 11-5, 18-16.
Pett (pictured in Santiago action against Coppinger) now faces local hero Borja Golan, the top-ranked Spaniard from Santiago de Compostela who downed club-mate Carlos Cornes Ribadas, the event's wildcard, 11-5, 11-4, 11-1.
There will also be English interest in the other semi-final where top seed Adrian Grant takes on Frenchman Gregoire Marche. Londoner Grant, the defending champion looking to make the final for the third year in a row, twice had to fight back from behind to see off New Zealander Campbell Grayson 9-11, 11-7, 8-11, 11-6, 11-9.
Unseeded Marche maintained his impressive Santiago run by following his first round upset over fourth seed Chris Simpson with a 10-12, 11-3, 11-8, 11-7 victory over higher-ranked Czech number one Jan Koukal.
 Adrian Grant (ENG) bt Campbell Grayson (NZL) 9-11, 11-7, 8-11, 11-6, 11-9 (77m)
Gregoire Marche (FRA) bt Jan Koukal (CZE) 10-12, 11-3, 11-8, 11-7 (49m)
 Borja Golan (ESP) bt Carlos Cornes Ribadas (ESP) 11-5, 11-4, 11-1 (24m)
[Q] Olivier Pett (ENG) bt  Stephen Coppinger (RSA) 8-11, 11-4, 11-5, 18-16 (57m)
 Adrian Grant (ENG) v Gregoire Marche (FRA)
[Q] Olivier Pett (ENG) v  Borja Golan (ESP)