Lady Selkirk has already beaten the colts and geldings once at Flemington and is poised to do so again in the Silver Bowl Series Final.

Trained by Matthew Williams at Warrnambool, Lady Selkirk is nominated for Saturday's Silver Bowl Series Final (1600m) as well as the Rivette Series Final over the same distance.

While the Silver Bowl is an open three-year-old handicap, the Rivette Series in restricted to fillies.

"We thought she is better placed at the weights and against the boys, so we're going to go that way to the Silver Bowl Final," Williams said on Tuesday.

Dodging the Hawkes Racing-trained Euro Angel, who headlines nominations for the Rivette Series Final, is another factor.

Euro Angel was a convincing winner at Flemington last month in a race in which Lady Selkirk struck trouble at the 350m when a luckless seventh.

"We think Euro Angel will be very hard to beat," Williams said.

"Weighing it all up we thought the Silver Bowl was probably the best way to go."

Acceptances for Saturday's races are taken on Wednesday.

After her Flemington run two starts ago where she had excuses, Lady Selkirk returned to the same track on June 25 to win a 1600m-handicap for three-year-olds.

Craig Williams takes over from apprentice Michael Dee in Saturday's non-claiming race.

Six of the first seven horses from Lady Selkirk's last start are nominated for the Silver Bowl Final including the Darren Weir-trained gelding Justa Hint who finished second.

Matthew Williams takes confidence from that race heading into Saturday, with Lady Selkirk one of only three fillies among the 18 nominations.

"We thought, and Craig thought, that on equal terms if she arrives at Flemington the way she did last start that she'd have the boys' measure that she has raced against," the trainer said.

"The wildcard is Adam Trinder's horse, Jerilderie Letter. But he's got to back up from Caulfield last Saturday."

Tasmanian Derby winner Jerilderie Letter was an eye-catching fourth over 1200m at Caulfield after covering ground from a wide barrier.

Williams believes Lady Selkirk, a half-sister to multiple city-winning stablemate Turnitaround, continues to improve.

"She galloped this morning on the course proper at Warrnambool and we feel she's actually come on and is going better again," he said.