There is only one side in League One who have yet to taste defeat this season.
And Sunderland are the next opponents for Pompey, who make the long trip north to the Stadium of Light this weekend.
They go there on the back of an impressive midweek victory at Gillingham, which came courtesy of goals from John Marquis and Michael Jacobs.
Joe Gallen now expects a sterner test on Wearside, but believes the Blues should be relishing the contest.
Pompey’s assistant manager said: “To go to Gillingham and play how we did was very pleasing. Obviously winning was the priority, but a performance like that provides confidence.
“We’re now expecting a tough game at Sunderland this weekend, but belief is high and we seem to be doing better away from home.
"Like us, they’re very well supported and – a bit like ourselves – are hoping not to be at this level for too much longer."
“It’s always a great opportunity for us to go there because they are one of the big clubs in this division.
“Like us, they’re very well supported and – a bit like ourselves – are hoping not to be at this level for too much longer.
“It’s a privilege to be involved in matches like this and our players should be looking forward to the challenge of going there and trying to win.
“We always know that if we play to the level we’re capable of, then we can beat anyone in this league.”
Gallen is extremely disappointed that a match of this magnitude is having to take place behind closed doors.
He said: “Sunderland are one of the biggest clubs outside of the Premier League and it’s just a shame there won’t be any fans to enjoy the occasion.
“We’ve missed the crowd at home – there’s no doubt about that. But I’m sure it’s the same for everyone else.”