Gemma Tattersall says potential selection for the 2016 Olympic Games is "beyond her dreams" after she finished as the highest-placed Briton at Badminton Horse Trials.
Tattersall, 31, placed third on Arctic Soul.
It was her best display at the prestigious championships and hit the Rio qualification standard.
"It is my absolute dream to get to Rio," said Tattersall, who took up riding aged 18 months.
Team GB's eventing riders will be chosen in July from those with the adequate criteria.
A group of four horse-rider combinations plus one reserve will be selected for August's Games.
"It's something I've been aiming for in the last few years in prepping this horse," added Tattersall, who finished behind winner Michael Jung and his German compatriot Andreas Ostholt at Badminton.
"If it comes off, it comes off. If not, I'll have to make the next one."
Are Team GB Rio medals likely?
After a team silver behind Germany at London 2012, eventing holds a real medal prospect for Team GB at Rio 2016.
There is no shortage of horse-rider combinations in line for selection.
Zara Tindall - the Queen's granddaughter - hit the qualification mark at Badminton on High Kingdom, the horse she guided into the team medals at London 2012.
Izzy Taylor on Allercombe Ellie, Laura Collett (Grand Manoeuvre), Ben Way (Galley Light), Francis Whittington (Hasty Imp) and Kristina Cook (Star Witness) also hit the qualification target at the Badminton Park event.
It all leads to tough decisions for selectors, who could also turn to William Fox-Pitt, the 2015 Badminton winner.
Fox-Pitt, 47, withdrew from this year's competition but boasts experience in the shape of four Olympic Games appearances which have delivered two silver medals and a bronze.