Cairo, Sept 15: The two top seeds in the Al-Ahram World Open squash championship, Canadian Jonathon Power, the holder, and Scotland's Peter Nicol, were both strongly challenged in the quarter-finals yesterday. Power won 15-8, 9-15, 15-7, 15-12 against sixth-seeded Englishman, Simon Parke, but incurred his second conduct warning of the tournament for continuous dissent.Nicol had to weather two bursts of swashbuckling squash from unseeded Mark Chaloner of England, a quarter-finalist in 1995.