Pompey won six of their past eight matches to end the year inside the League One play-off places.
And now they will look to remain there by beginning 2018 with a New Year’s Day victory at Bristol Rovers.
The hosts are down in 16th position and without a win in four games following Saturday’s stalemate with Oldham.
Joe Gallen believes they still pose a threat, however, and does not want the Blues to let their standards slip.
Pompey’s assistant manager said: “We’ve taken six points from the previous two games, so we’re going into this one with a lot of confidence.
“And so we should because the performance at home to Northampton on Saturday was a very good one.
"We’re going to need to play well and work out what we’ve done so well in recent weeks."
“There were numerous chances created and we were a bit unlucky not to come away with an even bigger victory.
“But going away to Bristol Rovers is always a tough fixture – certainly since I’ve been involved in football.
“They’re a team that can really take you apart, although they’re quite open and have had a few results go the other way as well.
“There are some really dangerous players in their squad, such as Harrison, Gaffney and Bodin up front.
“We’re going to need to play well and work out what we’ve done so well in recent weeks, making sure that we stick to that.”
Danny Rose and Gareth Evans limped off injured against Northampton, but Gallen believes Pompey can still hurt Rovers
He said: “Our squad is pretty depleted at the moment, but there is quality to come from the bench and players who can win us the game.”