Australia's Nick Kyrgios has beaten Matt Ebden in three sets to go through to the quarter-finals of the Brisbane International, but only after having an injury scare with knee problems.
Kyrgios caused concern when he had to receive medical attention, but played on to seal a 6-7 (7/3), 7-6 (7/5), 6-2 victory.
Games went on serve for the entire first set on Pat Rafter Arena, with Kyrgios and Ebden both holding serve repeatedly.
But towards the end of the set, Kyrgios called a medical timeout at 4-5 down on serve, complaining of a sharp pain in his left knee when he straightened it.
Kyrgios has been off the circuit since October to rest up for the Australian Open after struggling with shoulder, hip and knee issues in 2017.
But within his first set of competitive singles tennis for 2018, his knee had a familiar look, being taped up by the trainer.
The Canberran held on to take the set to a tie-break, but he quickly went down 4-1 in the breaker before losing 7-3 to go a set down.
Kyrgios tried a stand-and-deliver approach in set two, clearly unsure of how steady his knee was. He went for bigger serves and tried to shorten points to avoid having to run and turn too far.
Games again went on serve, with Kyrgios making little impression on Ebden's serve but holding his own to set up another tie-break. This time Kyrgios was the one who started strongly, and he ended up taking the breaker 7-5 to level the match.
Kyrgios was under real pressure on serve in the second game of the deciding set, coming from 15-40 down to hold for 1-1.
He then made Ebden pay for his inability to get the break, winning the third game to 15 to take the advantage.
Kyrgios continued to hold serve, and — looking more mobile as his confidence increased — he took a secure hold on the match with a top passing shot to break Ebden again to lead 5-2.
He then served out the match to make it through to the quarter-finals, where he will face Ukraine's Alexandr Dolgopolov, who beat Argentina's Horacio Zeballos 6-1, 6-2.