Lucas Moura believes Manchester City and Liverpool are beatable but warns Tottenham must avoid dropping "stupid points" to challenge for the Premier League title.
Spurs finished 26 points adrift of the top two last term as the champions and runners-up lost only a combined five matches.
Mauricio Pochettino's men managed to eke out a 2-2 draw away to an in-form City on the second weekend of the new season despite being outplayed for long periods, with Lucas securing a point when he nodded in Erik Lamela's corner.
However, the Brazil international thinks Sunday's home match against struggling Newcastle United is every bit as important if Tottenham are to keep the division's standout sides in sight.
"It will be so difficult, they are favourites, but I think in football everything is possible – there is no invincible team," Lucas told the Observer.
"Everything can happen and we need to believe that. We went to City and got a good result. We cannot lose stupid points at home as we did last season.
"My objective and our objective is to win a trophy. We have a very good squad, an amazing structure, a lot of fans and we can dream of a trophy. I think it is possible and we will try."
Lucas scored at the Etihad Stadium just 19 seconds after being introduced as a 56th-minute substitute.
The former Paris Saint-Germain forward has developed a reputation for making important contributions off the bench but hopes not to be pigeonholed as a super-sub.
He was forced to settle for a cameo role in the Champions League final loss to Liverpool even after scoring a scintillating hat-trick in the semi-final triumph over Ajax.
"Of course, I was sad inside. I want to play," the 27-year-old said.
"But I know how to understand, I know how to respect and I know how difficult it is for [Pochettino] to choose 11 players. So that's football.
"We need to be professional and keep working."
He added: "I do know that the season is long, that there are a lot of games and I will have my opportunity."