Phil Brown believes Pompey’s players are struggling with the pressure of representing their club.
The Southend boss brings his team to Fratton Park tomorrow on the back of one defeat in their past 12 matches – a run which has lifted them into sixth in the League Two table.
In contrast, the Blues have not tasted victory since November 22 against Morecambe – eight matches ago.
It is a disappointing spell which has prompted some fans to call for Awford’s head, with an element also booing at the final whistle of last weekend’s 1-1 home draw with Burton.
And Brown is convinced Pompey’s so-far disappointing campaign is down to a failure to cope with the club’s history.
The Shrimpers’ manager said: ‘Every time we’ve played Portsmouth we seem to put our best foot forward and that seems to be their biggest problem – every time a club plays them they know they’re playing a giant.
‘Their level of support is massive and they won the FA Cup not so long ago, that kind of history doesn’t go away.
‘I think it’s the pressure of playing for Portsmouth that seems to be the problem for them.
‘They’ve not really grabbed hold of League Two this season which has surprised because I really thought they would.
‘Andy has got his feet under the table, he knows his squad but he’s also tinkering a bit and has brought in one or two fresh faces.
‘He’s brought (Paul) McCallum in from West Ham who we looked at a couple of times before deciding he wasn’t really for us.
‘They signed Matt Tubbs and that’s one hell of a signing. For me that’s a signal of intent so it won’t be an easy game.’
Southend defeated the Blues 2-0 at Roots Hall back in September.
Awford still regards that day’s lacklustre display from his side as one of his biggest disappointments from this season.
Barry Corr broke the deadlock on 56 minutes, before Shaquile Coulthirst added a second in stoppage-time to wrap up the triumph.
The Shrimpers also won on their most recent visit to Fratton Park on November 2013, when Awford was caretaker boss before the appointment of Richie Barker.
Despite a goal down and reduced to 10 men, the visitors netted twice in the final 14 minutes to claim an unlikely victory.
Brown added: ‘Last year winning at Portsmouth with 10 men was a massive springboard for what we went on to achieve.
‘Hopefully, it can be a similar story this year too.’