John Mousinho has confirmed Portsmouth have suffered a "huge" injury blow with Bristol City loanee Rob Atkinson and Hayden Matthews both set for extended spells on the sidelines.

Atkinson departed Ashton Gate on loan during the January transfer window alongside fellow senior players Fally Mayulu and Kal Naismith who joined Sturm Graz and Luton Town respectively. Having not featured for the Robins for almost two years following an ACL injury and subsequent hamstring issues, City opted to allow the centre-back to spend the second half of the season at Fratton Park to build his match fitness and help him rediscover confidence in his body.

Until last week, the temporary switch had had the desired effect. The 26-year-old came through eight Championship games unscathed and helped Pompey put a gap between themselves and the relegation zone. However, the 26-year-old was forced off in Mousinho's side's win over QPR and while the Portsmouth boss pointed to some "positive signs", Atkinson was missing from the matchday squad for Saturday's defeat to Luton Town.

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After the full-time whistle at Kenilworth Road, Mousinho provided an update on the fitness of both the City loanee and fellow defender Matthews. While the latter's season has been ended prematurely, Atkinson's issue is expected to rule him out for a shorter length of time.

"Hayden’s out for the season and is going to need surgery on his ankle," Mousinho told Portsmouth's media team on Saturday afternoon. "It’s very similar to the issue that Connor Ogilvie had last term and he should be absolutely fine for next season.

"Unfortunately, Rob will also be sidelined for around six-eight weeks with a soleus [calf muscle] injury. It’s a huge blow because the centre-back partnership they formed, albeit very briefly, was very positive. To lose them – on the back of Conor Shaughnessy’s injury as well – is, of course, very disappointing for us.”

With just 11 matches left of Portsmouth's Championship campaign, Mousinho's side currently sit 17th in the table and eight points clear of the relegation zone having won promotion as League One champions last season.

Pompey's final game of the season will see them welcome relegation-threatened Hull City to Fratton Park on Saturday, May 3. With just nine weeks to go until the final weekend of the regular season, it is unclear whether or not Atkinson will be ready to feature for his loan club before the end of the campaign.

In the 26-year-old's absence, former City midfielder Marlon Pack started at centre-back in Saturday's defeat to the Hatters. The 33-year-old was deployed in that position when the Robins travelled to Fratton Park in December and when Portsmouth made the trip to Ashton Gate to mixed results. However, the former Reds' captain's displays in that position earlier this season have encouraged his manager.

“We looked at the four previous games they’d played together," Mousinho said whilst explaining his selection decision. "Preston, Swansea, Bristol City and Norwich, and they did really well.”

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