The 30-year-old is concerned with the Welshman’s likely two-week absence from the Spurs line-up due to a hamstring problem picked up during his side’s visit to Craven Cottage
The England international scored a double against London rivals at Craven Cottage, netting first after 72 minutes before firing home again just five minutes later.
Gareth Bale limped off with a hamstring injury during the clash much to teammate Defoe's disappointment, but the striker feels that Andre Villas-Boas' squad has enough quality to make sure results do not suffer.
"Obviously Gaz [Gareth Bale] is a massive blow for the team," Defoe told Absolute Radio's Rock 'n' Roll Football with Ian Wright. "The way he plays you can't really replace a player like that, but at the same time I think someone else can come in and do a job for the team.
"Luckily enough we've got a strong squad, we've got some great players, players that can come in and players that can play out of position, players that can adapt and do a job for the team."
Spurs boss Villas-Boas was the subject of much speculation following a poor start to their Premier League campaign, but Defoe insists that he is not under pressure at the club.
He added: "Obviously there's times like at the beginning of the season when we weren't really getting results and he was getting a little bit of stick and to be fair he's always been calm, always been calm.
"He's been in training and you'd never look at him and think 'this is a man under pressure', he's always been calm and in training as well and now we're getting results."