At the BWF Denmark Open, top seed An Se Young advanced to the women's singles quarterfinals by coming from behind to beat Thailand's former World No. 1 Ratchanok Intanon on Thursday.

After winning gold at the Paris Olympics this summer, An took a break and this tournament marked her return to the international stage. 

Intanon won the first game 21-17, but the South Korean came back to win the next two 21-18, 21-14 to secure her place in the last eight where another Thai player, Supanida Katethong awaits.

On the men's side, rising star Alex Lanier advanced to the quarterfinals after top seed and home favorite Viktor Axelsen was forced to retire due to illness during their last-16 match. 

The 19-year-old Frenchman was leading 21-19 and then 3-1 in the second set, when the two-time Olympic and World champion vomited, prompting medical assistance. 

The World No. 1 showed tremendous resolve in attempting to continue, but soon decided to retire while trailing 11-7 in the second game. Lanier will next face Singapoore's Loh Kean Yew.