St Kilda defender Sam Gilbert hails from a strong rugby league background, but the lean youngster is making his mark in the AFL.

Gilbert - whose grandfather and great-grandfather played for St George in the NRL - was named the round 16 Rising Star nominee on Tuesday.

It marks another milestone in the 20-year-old New South Welshman's rapid rise.

Gilbert debuted in round eight last year but managed just one more senior game in 2006, despite being named an emergency for the Saints no less than 12 times.

He earned his spot in the injury-riddled St Kilda line-up in round five this season and has not looked back, playing every game since.

In an important win against Hawthorn on Saturday night at Telstra Dome, Gilbert racked up 22 touches and hauled in 12 marks in an impressive display opposed to veteran Hawk Ben Dixon.

Gilbert said his solid run of matches had given him belief.

"It took probably the first 10 games before you do start to feel like you do belong (at AFL level). Now I am starting to feel I do," Gilbert said.

Gilbert's nomination comes just six years after switching from rugby league to the country's indigenous code.

As a junior he played rugby league for the Bilambil Jets following in the footsteps of this family.

A fullback for the Jets, Gilbert threw in his promising rugby league career and took up AFL.

"I started late in Queensland but I feel like I have been playing for ever now."

In 2005 he played in a premiership with Southport in Queensland and came under the radar of AFL recruiters with impressive performances for Queensland at under-21 level.

He also represented the Allies against Victoria before attending the AFL draft camp.

He was St Kilda’s first selection (33rd overall) in the 2005 national draft.

Gilbert is St Kilda’s first nominee since Raphael Clarke in Round 22, 2005.