Left panels: a Hertzsprung-Russel diagram (top), and the T_eff vs. radius diagram (bottom) showing the stellar evolution of the primary and secondary components of V2368 Oph. It was computed with the MESAstar module, for the masses M₁ = 2.62   M_⊙, M₂ = 2.74   M_⊙ and for the metallicity Z = 0.02. The evolutionary tracks are plotted by thick lines from ZAMS up to the age 3.877 × 10⁸   y. The ranges in temperatures T₁, T₂, luminosities L₁, L₂ and radii R₁, R₂ inferred from photometry/spectroscopy are denoted by lines (refer to Table 6). There is a strong disagreement between the observations and the stellar evolution, especially for the primary. Right panel: same for the masses M₁ = 2.682   M_⊙, M₂ = 2.678   M_⊙ (i.e., the mass ratio very close to one), and a different value of the metallicity Z = 0.014. The thick lines are terminated at the age 3.938 × 10⁸   y.