Buchan was thrilled with the Sundon filly's brave effort at Forbury Park last week when she sat parked for all of the 2200m journey and battled on to run second behind Easy Option.
The 3yr-old is yet to return a winner's cheque from 10 starts, but has been runner-up three times, and Buchan would love to get two wins with her before turning the filly out for the rest of the winter.
''I'll try and win two with Sappy's Brite Star as she gets the second one free [due to 3yr-old concessions],'' he said.
Buchan bases his age theory on Sappy's Brite Star's mother, Sapient, whom Buchan trained to six wins from 80 starts, although the daughter has already shown him she is not lacking in speed.
''She can actually trot faster and is a lot quicker than what Southland Reflector and the others are.
''As she gets older, she'll get a lot better.''
Sappy's Brite Star is one of the few runners in the 2200m maiden trot with form to speak of, although Lucie de Gerolstein continued her improvement with a good second at Winton on Sunday.
Southland Reflector may be outgunned by Sappy's Brite Star some time in the future, but Buchan is pleased with the majority of the 4yr-old's season - although there were excuses for his third at Forbury Park.
''Robbie [Close, driver] said he lost a shoe on the last bend.
''He'd been trotting really good and then [Robbie] said he just started hanging in on him, so he couldn't drive him out as good as he thought he could.''
Buchan might opt to get some cover with the son of Pegasus Spur after he showed a preference for chasing at Oamaru on May 19.
''If he steps good, I'll get him in front for a bit, and then I might drop him back a bit as he went really good at Oamaru coming from the back.
''He's been in front a few times and they've got to him in that last bit but maybe he's just better from behind.''
