Emmanuel Adebayor has highlighted what he believes to be the fractious state of Manchester City's dressing room, a tension he claims can rise to the surface in "a fight or an argument on the pitch" at White Hart Lane on Sunday.

The Tottenham Hotspur striker spent 18 months at City, after his £25m transfer from Arsenal in July 2009, and he rubbed shoulders with plenty of strong personalities, although many have since departed the club. Adebayor feels that Sunday's Premier League game is "decisive" for Tottenham's Champions League hopes and he believes that his team can profit from the fallout if City were to be frustrated.

"We are playing in front of our fans, we'll give them everything, put Man City under pressure and then for sure, we have a chance to win because I was there and whenever things are not going their way, there will definitely be a fight or an argument on the pitch," Adebayor said. "That is how we can take them down."

Adebayor scored 14 league goals in his debut season for City but his relationship soured with the manager, Roberto Mancini, who replaced Mark Hughes in December 2009. Adebayor spent the second part of 2010-11 on loan at Real Madrid before joining Tottenham, initially on loan, but he maintains that he does not "have anything to prove" to City or Mancini.

"Man City is a sacred club," Adebayor said. "I have a huge respect for the players. I've got players there that I can call family – Yaya Touré, Kolo Touré, Vincent Kompany. It's going to be important for me to prove how good I am but I don't have any pressure that says I have to beat Man City because of the way they treated me, because they bought me expensively and sold me for cheap.

"Mancini? We are all human beings. We are all adults. Things happened in Man City. I cannot tell you what happened and what did not happen. For me today, I move on. He has moved on. I wish him the best of luck. For me now, Mancini is just a manager I respect, just like Arsène Wenger, like Harry Redknapp and that's it. Everything stops there. I have to do my job for Tottenham."

The club, who are anxiously waiting on the availability of Gareth Bale after ankle damage, have endured a rocky ride in recent weeks. Their previous match was the Europa League quarter-final second leg against Basel last Thursday, when Adebayor missed one of their penalties as they lost the shootout, while they have taken only four points from an available 12 in the league to imperil their push for a top-four finish. Adebayor is determined to inspire an upturn against City.

"This will be the decisive game for us," he said. "If we win, the confidence will be back, definitely. We will have a chance to finish in the top four. From the beginning of the season, our target was to finish in the top four. Now we are out of the Europa League, I cannot say it is a good thing but we have to focus on the league. We have five games to go and we tell ourselves in the dressing room that we have five finals. We have to play them as finals and if we find a way to be in the Champions League, for us it's a very good season."