The England striker has dropped out of Harry Redknapp's first-choice XI this season as he has struggled for goals, with only four in the league all campaign.
'I want to help the club achieve things, win trophies and get in the Champions League, but when you feel like you are working hard, training hard and being professional, and then for some reason you are not playing, it is difficult,' Defoe told Sky Sports News.
Firing blanks: Defoe has managed a paltry four league goals this term
'It is frustrating. At the end of the day I am ambitious. I want to play in every game and score goals, especially when you score goals for a fantastic club like Tottenham.
'I have always been like that from the first day I walked through the door and I truly believe that if I am playing games I will score goals. I think my record shows that.
'It has been really, really hard to be honest. Players come and go, that is just football and it is out of my hands.'
Net result: A rare Defoe strike hits the back of the net against Blackpool
The 28-year-old insisted he remains committed to Tottenham, but admitted he may have to reconsider his future if he cannot get back in the team.
'If you speak to any of the players and the fans, they will tell you that I am committed to the club,' he said.
'I love the club and I still get the same buzz that I did when I first walked out at White Hart Lane, which is important.
'But for me the main thing is playing football and if I am not playing football then I am not happy, because I love my football.'
Down but not out: The Spurs striker still gets a buzz playing for the club
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Source: Daily Mail
Source: Daily Mail