Given a smooth function U ( t , x ) U(t,x) , T T -periodic in the first variable and satisfying U ( t , x ) = O ( | x | α ) U(t,x) = \mathcal {O}(\vert x \vert ^{\alpha }) for some α ∈ ( 0 , 2 ) \alpha \in (0,2) as | x | → ∞ \vert x \vert \to \infty , we prove that the forced Kepler problem x ¨ = − x | x | 3 + ∇ x U ( t , x ) , x ∈ R 2 , \begin{equation*} \ddot x = - \dfrac {x}{|x|^3} + \nabla _x U(t,x),\qquad x\in \mathbb {R}^2, \end{equation*} has a generalized T T -periodic solution, according to the definition given in the paper by A. Boscaggin, R. Ortega, and L. Zhao [Trans. Amer. Math. Soc. 372 (2019), 677–703]. The proof relies on variational arguments.