The Welshman was forced off the pitch in Spurs' 3-0 win at Fulham on Saturday with a hamstring injury which is likely to keep him out of the next two fixtures.
Tottenham meets Panathinaikos at White Hart Lane in the Europa League on Thursday before the tasty league clash with Everton at Goodison Park next Sunday but Defoe feels there are enough good players to cover Bale's absence.
"Obviously losing Gaz is a massive blow for the team," Defoe told Absolute Radio.
"Because of 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.
"We're lucky because we've got some great players that can come in, play out of position, adapt and do a job for the team.
"When Gaz went off the pitch Clint Dempsey went over to the left-hand side and did well. I think we will be okay."