Lu progresses in Memphis
Fourth seed Lu Yen-hsun fought back from a set down to progress to the quarter-finals of the US National Indoor Championships.
Home qualifier Denis Kudla took the first set but the world number 54 came storming back to take the match 3-6 6-3 6-3.
There was better news for another American qualifier as Alex Kuznetsov overcame eighth seed Mikhail Kukushkin.
Kuznetsov lost the first set 6-2 but claimed the second easily before snatching the third on a tie break to seal a 2-6 6-3 7-6 (7/1) victory.