Hungary's Laszlo Cseh has claimed that he needs to swim under 51 seconds in order to win gold in tomorrow's 100m butterfly final at the World Championships in Kazan.
The 29-year-old clocked 51.03s in the semi-finals after swimming sub-51 in the heats this morning.
The USA's Tom Shields matched Cseh's semi-final time, and the Hungarian is wary of the threat posed in the field.
"It was a good 100m fly, but if I am to get the medal in the final, I need to swim under 51s," Cseh told Eurosport. "It is really tough and this 100 is much faster than two years ago."
Cseh won gold in the 200m butterfly final earlier in the week.
