Pompey halted their four-match winless run in the league with victory at Forest Green on Saturday.
And Sean Raggett wants to make sure they build on that success when Oxford head to the south coast.
It is the first of back-to-back matches at Fratton Park this week, with Shrewsbury the visitors a few days later.
But Raggett’s focus is on facing a United outfit who have been the opponents for some tight contests in recent years.
The defender said: “This is a great group of lads and when we’re on a disappointing run, the boys don’t get too down about it.
“We stuck together and work hard to get back to winning ways and that has definitely given everyone a lift.
"It’s usually a pretty lively match when we come up against them, so it’s one that I’m really looking forward to."
“Now we’ve got Oxford and every single game we have against them seems to have more of a derby feel to it.
“They’re a good side, even if they haven’t started the season as well as they would have liked. They’re still full of quality players.
“It’s usually a pretty lively match when we come up against them, so it’s one that I’m really looking forward to.”
It was Raggett who got the winner at The New Lawn, opening his account for the campaign by converting Owen Dale’s free-kick.
He said: “I always fancy myself to score a few throughout the season and was disappointed that I hadn’t managed to get one before.
“We wanted to get on the right side of the set-pieces because we’re a big side and are generally good in that area of the game.
“We’d let ourselves down in that area during the previous two games, but we defended well on Saturday.”