The Czech Republic striker has joined from Lyon initially until the end of the season, with the option of a permanent deal.
"The team is currently four points behind the Champions League places and, at the very least, everybody here thinks about the UEFA Cup," the 26 year old told MF Dnes.
"The league is even and a couple of clubs will fight among themselves until the very end.
"Each point will be important and I want to scramble for them for Portsmouth, although it will be no easy job."
Baros, who was also wanted by Lens and Sevilla, is looking forward to playing regularly after struggling for opportunities at Lyon this season.
He added: "I think I have made a step forward. Away from France, I am back in England where I know the language, the scene and the league.
"Moreover, Lyon have been playing with a lone striker and that is (Karim) Benzema.
"On the other hand, at Portsmouth I feel I will have a bigger chance to gain ground, which should also help me with regard to Euro 2008. The manager Redknapp wants me as well."
He concluded: "There will be a little bit of nostalgia. I am returning to the world's best league where the fans' support is best. I am looking forward to it."