Announced back in August, 2019, Cosgrove was one of 31 players selected in the Penrith Panthers squad for the upcoming 2020 under 18s tournament.

In his last endeavour into junior representative rugby league, Cosgrove also played for Penrith in the 2018 Harold Matthews Cup season.

His return to the junior representative rugby league level is a big win, considering the effort he's put in.

"It was unreal, I couldn't believe it," the St Pat's junior said.

"It was pretty much my goal for the whole year."

The kick-off to the new SG Ball Cup season is quickly approaching - Penrith start its season on February 8 - and Cosgrove's main focus is to now lock-in a starting role in his preferred centre position.

"So far I've only made the squad but now I want to crack down the starting position as a centre," he said.

"Just because I'm in the squad, there's no guarantee there's a start.

"Round one is in two weeks and we've got one more trial before it starts, so I want to be playing consistent footy and nail down that starting position."

He said that fullback would be an ideal back-up.

And while Cosgrove has ticked off his first goal - to be selected in the SG Ball Cup - he said his next task is to make the NSW team.

"We've got a couple of NSW guys in our team, so another goal for me would be to make NSW, try and make it in that team," he said.

"The goal for Penrith would be to make the grand final too.

"This team was in the under 16s the stage before [in 2018] and they won the minor premiership but just missed out on the grand final. It be great for us to come back this year and win it."

Penrith are one of the most successful SG Ball Cup teams, with the club's eight premierships the third best, behind Parramatta and South Sydney with 12 and 10 respectively.

Panthers' last premiership was in 2018, when they defeated Canterbury 25-14 at Leichhardt Oval.

Cosgrove will also continue to dedicate his season to St Pat's - the team he won a Group 10 under 18s premiership with in 2019 against Bathurst Panthers - and, if Penrith make the SG Ball Cup grand final, he will only miss about five games for his local side.

Panthers will open its SG Ball Cup season against Balmain at Leichhardt Oval.