Spectra of the H I (red), H₂ (blue) and ¹²CO (2–1) (black) gas extracted against the compact radio continuum emission of PKS B1718–649. Two separate lines are detected in the H I gas with opposite velocities with respect to the systemic. The ¹²CO (2–1) detected in absorption peaks at red-shifted velocities (Δv ~ 343 km s⁻¹) with respect to the systemic (black dashed line). The H₂ gas is detected in emission at the systemic velocity and at the velocities of the red-shifted absorption line of ¹²CO (2–1) gas. The spectrum of the H₂ gas has been normalized to the maximum of the spectrum of the ¹²CO (2–1) line (see Sect. 3.3 for further details). The shaded regions of the lines are tracing gas that is not regularly rotating.