SuggestedLeadIn: USA's LaShawn Merritt on his second place finish and the collapse of winner Wayde van Niekerk in the men's 400 metres at the World Championships in Beijing.

Script: SOUNDBITE: (English) LaShawn Merritt, 400 metres silver medallist:

"The event is really strong right now. I've had a rough season, trying to do some new things with a new coach. And I got hurt early on in the season. But there's no excuses when you get to a championship. You are here because you belong here. I know that I have been here before. And I went out and I did actually execute like I was supposed to. The last part of my race could have been a little better. I'm my worst critic. But I ran a personal best and I know I ran well. It just wasn't enough for the gold so I'll take the silver this year - and get ready to try and get the gold next year in Rio."

SOUNDBITE: (English) LaShawn Merritt, 400 metres silver medallist (on Wayde van Niekerk's condition post-race):

"He came off the track and fell down and the ambulance came and took him out on a stretcher. I wish him the best. Hopefully, nothing major."