$f(\mathsf{R})$ Gravity Wormholes sourced by a Phantom Scalar Field

We derive an exact wormhole spacetime supported by a phantom scalar field in the context of $f(\mathsf{R})$ gravity. Without specifying the form of the $f({\sf R})$ function, the scalar field self-interacts with a mass term potential that is derived from the scalar equation and the resulting $f(\mathsf{R})$ model is purely supported by the scalar field and it is free of ghosts and avoids the tachyonic instability.