Britain's Nick Skelton and Robert Smith put themselves in strong contention after the opening round of the Olympic individual show-jumping competition.
Skelton, with his horse Arko III, is in joint 11th place ahead of Tuesday's second round after incurring just one time penalty in Sunday's qualifying.
Smith, riding Mr Springfield, was inside the time allowed but had four faults for bringing down a fence.
He is in joint 19th, but still in touch with the 10 riders who went clear.
Skelton has arguably the best chance of an Olympic individual medal for Britain since Ann Moore won silver at the Munich Games 32 years ago.
"That was a great start for me," he said. "He is a fantastic horse and
certainly has the talent to compete with the best here.
"The round felt very good and I am not worried about the time penalty at this
stage, the important thing is to go clear.
"You need some luck though and hopefully we will get that, but we are very
pleased to be in the position we are in at this stage."
Smith, the son of Harvey Smith, is aiming to become the second member of his family to win an Olympic medal.
His brother, Steve, was part of the team which won silver at the 1984 Games.
Following Tuesday's second round, the final two rounds take place on Friday.