Casey leads Johnson by one in Valspar Championship

(Reuters) - Defending champion Paul Casey held on for a one-stroke third-round lead over world number one Dustin Johnson at the Valspar Championship in Florida on Saturday.

England's Casey shot 68 to top of the leaderboard at nine-under 204, but what had been a three-stroke lead dwindled to one after a bogey at the last.

Johnson applied the pressure with a 67 and fellow American Jason Kokrak (66) was close behind on 206, thanks in part to a hole in one at the par-three 15th.

England's Luke Donald and American Scott Stallings were also in contention after both shot rounds of 70 to finish on 207.

(Reporting by Gene Cherry in Raleigh, North Carolina, editing by Ed Osmond)