Josh Little, Ireland's 17-year-old left-arm quick, has put his education ahead of his cricket and pulled out of Ireland's squad for a T20I series against Afghanistan in India next month.
He has been replaced by Peter Chase, the Malahide seamer.
Little has already interrupted his studies for an Under-19 tournament in Bangladesh last year, as well as two T20s against Afghanistan and Namibia in the Desert Challenge in Abu Dhabi last month,
"Josh is only 17 and there were concerns about the time missed in what is a crucial period for his education," said Cricket Ireland's head coach John Bracewell.
Little became the second-youngest player to be selected for a Twenty20 international, behind Hong Kong's Waqas Khan, when he made his debut against Hong Kong in Bready last September.
Chase, 23, has yet to make his T20I debut for Ireland, but has played eight ODI's and one ICC InterContinental Cup tie.
Bracewell added: "Peter was impressive during the ODI series last summer against Afghanistan, taking seven wickets, and gets that crucial extra bounce with his height."
Cricket Ireland have also appointed former Leicestershire coach Ben Smith, 44, as consultant assistant coach for the tour to UAE and India. Andrew White, who fulfilled a similar role during the Desert T20, was unavailable for the tour due to work commitments.
Performance director Richard Holdsworth said: "Given that Peter Johnston is tied up in his role as acting national academy and performance manager, while Ryan Eagleston is preparing the Under 19's for their World Cup qualifiers as well as working with the emerging academy we felt we needed to go outside for this temporary role."
As well as coaching the first-team at Leicestershire, Smith has held roles with both Worcestershire and the ECB Development Squad. He is currently working in New Zealand as a specialist coach with Central Districts.
Ireland play the UAE in two ODI's at the ICC Academy 1 ground on March 2nd and 4th, before travelling to India to face Afghanistan in nine matches across three different formats.