And the Blues are monitoring defender Mullarkey, having watched him in action for the National League side.
The 25-year-old has been an ever-present for Altrincham this season, starting 42 matches and netting three times.
He is primarily a right-sided centre-half, which remains his favourite position, although has also served as a defensive central midfielder.
Certainly Pompey’s interest focuses on his defensive ability as they seek to bolster a back line which could well lose The News/Sports Mail Player of the Season Sean Raggett.
Mullarkey, who is out of contract in the summer, lined up for Altrincham in their 3-0 defeat at Notts County on Saturday which leaves them in 14th spot.
He was booked in the Meadow Lane loss, with Pompey target Kyle Wootton netting for the Magpies with his 21st goal of the season.
Mullarkey is viewed as a powerful central defender and regarded as one of Altricham’s leading performers this term.
He began his career at Crewe before released in the summer of 2016 at the end of his two-year scholarship.
After joining Leek Town, he progressed to Nantwich in 2017, amassing 88 appearances and four goals during a period which also saw him trial for Blackpool in November 2018.
In May 2019 he linked up with Altrincham, where, in his first season, he helped them into the National League through the National League North play-offs.
Mullarkey has now totalled 107 appearances and six goals for Phil Parkinson’s side, who have two matches remaining this season.
Altrincham are keen to retain the highly-rated defender and have tabled a new deal as they seek to take on full-time professional status next season for the first time in the club’s history.
However, should he reject terms, he will this summer become a free agent, with no compensation required for interested parties.
Cowley has previously spoken of Pompey’s thorough approach towards identifying talented non-league players to bolster his squad.
His first Blues signing was Liam Vincent in June 2021, taking him from National League Bromley for an undisclosed fee.
However, the teenage left-back has still to make his first-team entrance following an injury-wrecked introduction to Fratton Park.
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