Marshall has ridden 12 winners for Forster at a 20 per cent success rate.
As a combination the duo are showing a staggering $198 profit on a $1 the win unit on each of their runners.
Much of that windfall is attributed to Eelloh winning a two-year-old race at the Sunshine Coast at $10 in April.
Forster spelled Eelloh straight after that win to give her time to mature.
"She improved out of sight in a short time last preparation, she has had a good spell and trialled OK," Forster said.
"She just has a tricky barrier (10) on Saturday."
Boom Spender has drawn barrier five for his second run back from a spell.
"He was good when second first-up and I said before that run he was wanting the run," Forster said.
"Both horses are raced by loyal supporters of the stable and wins would be a nice way to end the season."
Forster's support has seen Marshall's profile blossom in recent months, a boost illustrated by his recent Listed Glasshouse Handicap win on Krone for top Brisbane trainer Tony Gollan.