Novak Djokovic recorded his eighth win in 12 meetings against Fernando Verdasco as he cruised into the Qatar Open quarter-finals on Wednesday.
Djokovic has not lost to Verdasco on hard courts since their first meeting at the 2005 US Open, a run of six successive matches for the Serbian.
His latest triumph was a comfortable 6-2 6-2 victory, although the Spaniard was able to put some pressure on his serve as Djokovic was forced to save two break points in the match.
The top seed - who is targeting a 60th ATP Tour title this week - will meet Leonardo Mayer in the last eight after the Argentinian beat Pablo Andujar 6-2 6-4 in his second-round encounter.
Former champion Rafael Nadal is also in the latter stages after crushing Robin Haase 6-3 6-2 in an emphatic victory for the 2014 winner.
Nadal had won his only previous meeting with Haase in 2010 at Wimbledon, and he never looked in danger against the Dutchman.
Having taken the first three games of the match, Nadal went on to wrap up his win with two breaks in the second set, while Haase failed to take any of the four break chances he was able to create.
Nadal's next opponent is Andrey Kuznetsov after the 24-year-old produced a stunning second set against Ricardas Berankis, the Russian winning four successive games to complete a 7-6 (8-6) 6-1 triumph.
Wednesday also saw victories for third seed Tomas Berdych, Jeremy Chardy, Illya Marchenko and Kyle Edmund - the latter edging a third set tie-break against Daniel Munoz de la Nava.