William Gallas claims he has joined a Tottenham side capable of winning this season's Barclays Premier League.
Gallas became the most high-profile player to cross the north London divide since Sol Campbell on Sunday when he signed a one-year contract at Spurs.
Campbell immediately helped Arsenal land the championship after completing his controversial move nine years ago.
And 33-year-old former Gunner Gallas believes it would not be impossible to mirror that feat at White Hart Lane this term.
"Finishing fourth last season shows Spurs have improved a lot and I hope this season we are going to finish even higher, maybe even win the Premier League," Gallas told his new club's official website, www.tottenhamhotspur.com.
"We just have to believe in ourselves. We have got young players with great quality.
"They just have to believe in their capacity to do something and I hope we can achieve this."
Gallas' controversial move is bound to go down badly with a number of Arsenal supporters, and perhaps even some fans of the team he has joined.
Manager Harry Redknapp revealed on Friday he had been in talks for some weeks with the versatile France defender, who it appears did need to be convinced to move directly from Spurs' arch-rivals after becoming a free agent this summer.
"It was not an easy decision but I am here now and I will give my best," Gallas said.
"What is most important to me is to play games and to give everything."
Gallas, who is two weeks away from being match ready, trained with his new team-mates yesterday.
He added: "I just want to be fit as soon as possible, train with my team-mates and play matches. I want to show everybody I am still here."
Gallas will miss tomorrow night's must-win Champions League clash with Young Boys but will feature if Tottenham overturn a 3-2 play-off round deficit and progress to the group stage.
"Spurs are ready for the Champions League, even though they lost the first game," said Gallas, who has played in Europe's premier club competition for the past seven seasons.
"It is the best level to play at as you are up against the biggest teams and you can show how good you are.
"The atmosphere is so great. When you hear the music, you just want to get on the pitch and battle for 90 minutes, and it would be good for Spurs."
Tottenham are still sweating over the fitness of a number of key players.
Jermain Defoe (groin) looks set to return but Luka Modric (groin), Roman Pavyluchenko (ankle), Giovani dos Santos (hamstring) and Robbie Keane (knee) all remain doubtful.
Indeed, Keane may have played his last game for the club following fresh reports Aston Villa and West Ham are preparing bids for the Republic of Ireland striker.
Press Association Sport understands Spurs could be tempted by an offer in the region of £10million for the 30-year-old.
Meanwhile Spurs midfielder Jamie O'Hara will undergo back surgery on Thursday.
The 23-year-old has been under the care of a specialist this summer after suffering a stress fracture last season.