Defoe, who has three goals in 15 league appearances this season, sustained the injury in Wednesday's defeat by Chelsea in the League Cup quarter-finals.
“The 35-year-old sustained the injury in a tackle in the opening minutes of the tie at Stamford Bridge... Defoe is expected to be sidelined for around eight to 10 weeks,” Bournemouth said on their website.
Despite the injury setback, manager Eddie Howe has no intention of delving into the January transfer market to look for a temporary replacements, give that he is happy with the options at his disposal in Defoe’s absence.
“The beauty of it is we do have a good array of options in the striking department - five strikers are quite a lot to carry,” Howe said this week, with Benik Afobe, Lys Mousset, Callum Wilson and Joshua King all candidates to replace Defoe – although King is currently sidelined with a hamstring complaint himself.
"Usually we play with two up front so I think that was a necessity. It would be a blow to lose Jermain for any amount of time but I think we've got the cover.
"Whoever we decide to pick, I think we've got the firepower to hurt anybody. Lys played against Chelsea and I thought he did well.
"Jordon Ibe played in a different role again and I thought he did well too. It proves we do have the quality.
"We maybe don't have the strength in depth in terms of number at the moment with the injuries but hopefully they'll be back soon."
A 4-0 loss to league leaders Manchester City on Saturday dropped Bournemouth into the bottom three. They face fellow strugglers West Ham United on Tuesday.
Join our new commenting forum
Join thought-provoking conversations, follow other Independent readers and see their replies