Boss Mick McCarthy is set to run the rule over the winger after he declared he wants to represent Eire.
He bolsters Kenny Jackett’s attacking options ahead of the Blues’ forthcoming League One promotion push.
After an impressive season at the Brewers, registered six goals and seven assists in 39 appearances, the 23-year-old caught the eye of McCarthy.
Harness has expressed his interest to play for the Green Army after scouts watched him for Nigel Clough’s men.
Ireland have a busy autumn ahead, with European Championships 2020 qualifiers against Switzerland (home and away) and Georgia, as well as a friendly with Bulgaria, in September and October.
McCarthy is keen to widen the pool of talent he can select from, with Harness one candidate identified.
And the Ireland boss will be assessing the Coventry-born ace’s performances at Fratton Park.
McCarthy said: ‘Terry Connor and myself both saw Marcus play with Burton last season and we will have him watched again when the season kicks-off next weekend and see how he gets on.
‘He has told us he wants to play for Ireland and we will follow through on that now and help him sort the paperwork from his side.’
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