DOHA: World No. 1 James Willstrop gave a warning he is developing his most significant world title challenge yet as he dispatched one of his friends en route to the quarterfinals here yesterday.

The thoughtful Englishman set aside amicable sentiments with a tight professional mindset during a 11-6, 11-7, 11-2 win against Saurav Ghosal, a regular sparring partner at their shared base in Yorkshire and the first Indian ever to make the last 16. But more than that Willstrop showed that he is adapting to the demands of an unusually testing cool court by producing a consistently immaculate length, yet varying the pace, and “holding” the ball to produce subtle disguises.

So far he has employed these classical skills better than anyone and, apart from a brief spell in the middle of the second game when the talented Ghosal sneaked a 6-5 lead, Willstrop controlled the match with masterful economy.

“When you go on court each day with each other and spend a lot of your lives together, it’s slightly difficult, but a lot of players have to get used to that — it’s part of the togetherness the tour brings,” Willstrop said.

“I felt I played really well. There was a lot of stuff going through to the back, but we were both hitting an attacking length, and it was focussed and punishing. I feel very good.” Willstrop will face a surprise quarterfinal opponent, the 15th seeded Borja Golan, the first Spanish player to get so far since Austin Adarraga 20 years ago.

Golan achieved this by bringing down the sixth-seeded Peter Barker, a teammate of Willstrop in England’s 2007 world title winning squad, with a typically tenacious 11-7, 4-11, 11-3, 11-3 triumph which would have seemed impossible three years ago when a knee injury almost ended his career.

“I didn’t think Peter was a hundred percent because he had a problem with a leg,” the Galician from Santiago de Compostella said generously, referring to Barker’s troublesome hamstring.

“But I tried to be focussed on my game.

“I remember Austin (Adarraga) very well because he was an inspiration to me. But I now have to win again if I want to equal what he did.”

Later at least one Egyptian semifinalist became certain when Karim Darwish, the fourth-seeded former world No. 1, came through to meet Mohammed El Shorbagy, the eighth-seeded former world junior champion.

Darwish saved a pivotal game point at 10-11 in the second game of a tough 80-minute battle with Daryl Selby, the former British national champion, narrowly prevailing 11-9, 13-11, 10-12, 11-9.

El Shorbagy, not long after completing three projects for his ongoing business studies degree at university in Bristol, England, got on top from the middle of the match in a 11-13, 11-6, 11-2, 11-7 win against the 16th seeded Cameron Pilley, the leading Australian.