Glamorgan look set to give 20-year-old spinner Kieran Bull his first senior game of the season against Gloucestershire in the Championship.
The experienced Dean Cosker has been left out of the squad for the game, which starts in Swansea on Thursday.
Bull and Andrew Salter are the specialist spin options on a St Helens ground where they have often fielded at least two slow bowlers.
"Kieran is a very attacking off-spinner," coach Toby Radford said.
"He's still at university... but continues to show great promise."
Glamorgan go into the match in third place in Division Two, but are 36 points behind Surrey after defeats against Essex and Lancashire.
Their One-Day Cup match against Sussex was washed out after just six overs, while Gloucestershire arrive in Wales on the back of a four-wicket victory away to Worcestershire.
Glamorgan are likely to restore Mark Wallace behind the stumps after he was rested for the first time in four years against Sussex.
Aneurin Donald, 18, is looking forward to a chance to perform in Swansea, near where he was raised in Gorseinon, in his last match before leaving to captain England Under-19s against Australia.
"It's usually a result wicket down here and I believe Gloucestershire could have a few key players out as well, so it's another big game for us," Donald said.
"It's going to be another good chance for our spinners later on in the game and it's always been a pretty good hunting ground for us.
"Kieran did well for us last year in a few Championship games, he's a great spinner and a very good four-day bowler which is probably his strong suit at the minute, spins it quite hard."
Donald admits he has played more rugby than cricket at St Helens before this week, after representing Swansea in age-group schools teams at inside-centre or fly-half.
"It's a big pitch, a wide pitch, it used to be tiring but it used to suit our game," he added.
"It was always a great place to come and play rugby under the lights but it's a great place to play cricket as well."
Donald is scheduled to leave Swansea directly after the game to travel to the north of England for the first of a five-game limited-overs series against the touring Australian youngsters on 11 August.