Great Britain finished the opening day of the dressage competition in the bronze medal position.
Team GB were not expected to be in the medal hunt in this event, but Carl Hester's score of 70.6% and Emma Hindle's mark of 67.5% gives GB hope.
Germany lead on 71.813 points, the US are second on 69.146, while the British quartet are just behind on 69.084.
Richard Davison, partnering Ballaseyr Royale and Nicola McGivern on Active Walero, are in action on Saturday.
Hester's brilliant mark on Escapado puts him in fourth in the individual standings.
Meanwhile, Hindle, who partnered Wie Weltmeyer, is in 11th.
A delighted Hester said: "That was such a fantastic performance from the horse.
"I was nervous at the start of the test and when the crowd started cheering
he got nervous as well.
"But he is a very talented horse and was just brilliant
"It was decided in the team meeting that I should go first because this is my
fourth Olympics but I didn't really want to go first. But it worked and I am
delighted with that."
Spain's Rafael Soto, riding Invasor, leads the individual standings, having been awarded 72.7% for his display.
Germany's Hubertus Schmidt with 72.3% and Heike Kemmer on 71.2% are second and third in the individual competition respectively.
The Olympic dressage competition involves several phases.
The first round, known as the Grand Prix, takes place over two days and
determines the winners of the team competition.
The individual places are then decided over two further rounds comprising of
the Grand Prix Special, taking the top 25 riders from the team standings.
A cut is then made and the top 15 move through to the Grand Prix final freestyle
round on the final day.