David Eustace has been taken by the physical improvement in Ideas Man and the co-trainer believes that added maturity will show when the colt puts his Blue Diamond credentials on display in the Chairman's Stakes at Caulfield.

Ideas Man was a narrow but impressive winner of the $500,000 Inglis Banner (1000m) at The Valley in October at his only start.

The talented colt features among a number of juveniles trained by Ciaron Maher and Eustace being aimed at the $1.5 million Blue Diamond (1200m) at Caulfield on February 22.

Ideas Man is at $21 in Blue Diamond betting and Eustace believes he has made the necessary improvement to be a candidate for Victoria's premier juvenile race.

"I think he's improved a lot physically. He has really strengthened up," Eustace said.

"It's hard to weigh up that race (Inglis Banner). History tells you it's probably not that strong but I thought he was pretty impressive and I really like the way he has matured physically.

"And his work has been really good."

Ideas Man is among a host of juveniles in Saturday's race who hold Blue Diamond entries.

The Mick Price-trained Extreme Choice won the Chairman's on his way to Blue Diamond success four years ago.

Ideas Man will be striving to give Maher and Eustace back-to-back wins in the Chairman's after star filly Loving Gaby kicked off her career with victory 12 months ago.

Loving Gaby was an unlucky sixth in the Blue Diamond at her next start.

Ideas Man is on the second line of betting for Saturday's race at $4.20 behind stakes winning filly Aryaaf ($2.90) from the Lindsay Park stable.

Aryaaf defeated the Maher and Eustace-trained Blue Diamond hopeful Muntaseera in the Group Three Ottawa Stakes at Flemington in her only race appearance in the spring, despite racing greenly over the final stages on the straight course.