The former West Ham boss made his return to Fratton Park a year after departing and taking on the job at rivals Southampton. With Pompey on the back of four straight defeats - with ten goals conceded and one scored - Redknapp quickly needs to inspire his mostly new charges in order to ease out of the relegation zone.
JJ does expect the visitors to be lifted by the change at the top but insists it is all about us as we chase a hat-trick of wins after recent victories over Wigan and Sunderland.
"There is always some kind of reaction when a team gets a new manager and we know it is not going to be easy for us," considered the midfielder.
"We have had two good wins now, although we made it a bit difficult for ourselves in our last game against Sunderland, and hopefully that will continue.
"I have been slightly surprised by Portsmouth's position this season, although I don't know what goes on down there and can't really offer an opinion on it. The Pompey teams you come across are usually good sides and I am expecting no different when we come up against them on Monday night."
With attention sure to be zoomed in very much on Harry and Portsmouth tonight, JJ suspects this will provide the opportunity to go quietly about our business and get on with the job of ensuring we retain our position in the Premiership's top four.
"The focus has been on Pompey for the last week with the manager situation and now Harry has come in I'm sure there will be more focus on them. It is up to us to concentrate on our game and make sure we go about the job properly."
Jermaine Jenas is anticipating a positive reaction from the Pompey players tonight following last week's appointment of Harry Redknapp as manager.