Top seed shuttler Chen stunned out by teammate Xue at All England

China's top ranked player Chen Long was shocked by teammate Xue Song in the second round of the badminton All England Championships here on Thursday.

The defending champion Chen became the second big name to fall following second seed Lee Chong Wei's early exit in the first round one day earlier.

Chen, winner here in 2013 and 2015, was beaten 21-19, 21-17 as the 22-year-old Xue, ranked a distant 30th, advanced to the quarterfinals in barely believable style

"I have to say that top seeds losing early means that the general standard of men's singles is very high," Chen told.

"I think that I am feeling well but I will have to go home and find out what went wrong today."

Xue, a close friend of Chen, said: "When we play on court we couldn't fully play out what we're capable as we know each other's game so well. I had all the luck."

China's Lin Dan, the five-time champion, advanced to the men's quarterfinals rallying past Japan's Sho Sasaki.

Fifth-seeded Lin fought back from one set down to win 20-22, 21-6, 21-8.

"It took me time to get into the match but I changed my tactics, stayed calm and I'm really happy to get through," Lin said.

He will now play Denmark's Jan O Jorgensen, the 2015 finalist, while Xu take on another Dane Victor Axelsen. Endit