Sophie Wells won Great Britain's third equestrian medal of the Paralympics at Greenwich Park.
But the 22-year-old could not emulate her fellow Paralympic debutant Natasha Baker, who landed the Grade II individual title on Saturday, in taking gold.
Wells, from Newark in Nottinghamshire claimed silver behind Belgium's Michele George, a Grade IV result that was reversed from the 2010 World Equestrian Games in Kentucky.
Wells, who was born with amniotic band syndrome that affects her joints, is such an outstanding dressage talent that she has also competed at non-disabled international level. But a mistake midway through her test here on Pinnochio cost her dear as their score of 76.323% fell short of George's 77.065% aboard Rainman, with Dutch rider Frank Hosmar and Alphaville taking bronze.
Wells' display, though, tightened the British grip on team gold after they took a commanding lead into the final day of that competition.
Wells, whose test came immediately after George's, struggled to conceal her disappointment at not securing a Paralympic individual gold, although she will be a leading contender in Tuesday's freestyle to music class.
There was more British medal success in the Grade III class, where 46-year-old Deborah Criddle won silver with LJT Akilles.
It also meant that Britain had an unassailable lead in the team competition, although no official confirmation of their fifth successive Paralympic title was expected until later today.
The team of Criddle, Wells, Lee Pearson and Sophie Christiansen preserved an unbeaten Paralympic record that began in Atlanta 16 years ago.
Although Criddle's test contained some mistakes, a score of 71.267% set the standard and was not overhauled until penultimate rider and defending Paralympic champion Hannelore Brenner posted 74.133% with Women of the World.