Kyle Edmund battled past Austrian qualifier Dennis Novak in three tie-break sets to reach the Erste Bank Open quarter-finals in Vienna.
The British No 2 was made to work hard against the world No 284 but eventually prevailed 7-6 (7-2) 6-7 (7-5) 7-6 (7-3) in composed fashion to avoid a shock defeat.
Edmund, the world No 63, was broken as he served for the first set, but responded immediately and managed to win the opener on a tie-break.
Both players claimed a break of serve apiece in the second before Novak eventually took the match into the third set after claiming the second in another tie-break.
The deciding set remained on serve for the entirety so a deciding tie-break was required which Edmund took the initiative in when Novak misjudged an attempted drop shot before he closed out the match.
Edmund will next face Jan-Lennard Struff after the German world No 51 progressed with a 6-7 (7-5) 6-2 7-6 (7-1) hard-fought victory over Albert Ramos-Vinolas, the Spanish world No 22, who was unable to back up his opening round victory over American sixth seed Sam Querrey.
Meanwhile, Pablo Carreno Busta's hopes of reaching a maiden season-ending ATP Finals in London were hit by a three-set defeat to Diego Schwartzman.
The Argentinian world No 26, who reached the US Open quarter-final at Flushing Meadows, secured an impressive 5-7 6-1 6-1 victory over his Spanish opponent to book a quarter-final meeting with Philipp Kohlschreiber.
Lucas Pouille booked his spot in the last eight with a 6-3 7-6 (10-8) win over Spanish qualifier Guillermo Garcia-Lopez and will next meet Richard Gasquet after he knocked out home favourite Dominic Thiem 4-6 7-5 6-1.
Jo-Wilfried Tsonga, fresh from his European Open triumph in Antwerp last weekend, was made to work hard for his 6-7 (7-5) 7-6 (9-7) 6-1 victory over Bosnian Damir Dzumhur and now faces a high-profile quarter-final clash against top-ranked Alexander Zverev from Germany.
Sky Sports has all the action from the Erste Bank Open in Vienna and Swiss Indoors Basel this week before the Paris Masters.
The Next Gen ATP Finals in Milan and season-ending extravaganza ATP Finals at London's O2 in November end another memorable year which will be covered via our website sky.mnosports.com/tennis with live blogs and updates as the season reaches its climax.
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