Mo Farah has admitted that his victory in the 10,000m World Athletics Championships final in Beijing was tougher than his triumph at the 2012 Olympics.
The 32-year-old retained his title from 2013 as he beat Kenya's Geoffrey Kamworor in a sprint finish, running the final lap in 54 seconds to claim the crown.
"I knew the guys were going to do that, too many years now they've left it slow so they had to do it and it did happen," Farah told BBC Sport.
"It was a matter of digging in and hopefully it didn't take too much out of me for the 5,000m. It's not easy running 27 minutes in this heat.
"The last lap, that was close - I honestly thought at one point I was gone because I stumbled. The Olympics were pretty tough because of the pressure and being at home, but at the same time it was never that quick."
The gold medal was Great Britain's first of the Championships.