The News understands the 29-year-old is negotiating a switch to fellow League One club Lincoln.
Marquis was absent from training this morning ahead of tomorrow night’s trip to AFC Wimbledon, with Academy striker Dan Gifford stepping up to boost numbers.
It is believed the former Millwall man has been given permission to seal his Fratton Park departure, which will effectively mean he has played his last game for the club.
The striker is surplus to requirements at Pompey and, being out of contract in the summer, has been told he will not be offered a fresh deal.
The Blues have been eager to offload their top earner in January to create space within their playing budget to strengthen, particularly the striking department.
It is not currently clear whether Marquis’ exit will be a loan or permanent arrangement, yet Pompey will be called upon to make some sort of financial contribution to make-up his wages.
He had been interesting League Two Mansfield, yet it is understood the centre-forward will be remaining in League One.
Marquis made his 127th appearance for the club after appearing as a substitute in Saturday’s 2-1 defeat to MK Dons.
Over two spells, he has netted 38 times, while was last season’s top scorer.
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