Asymmetric CO ro-vibrational line profile in a circularly Keplerian disk with a gap between 0.8−2.8   AU (similar to model #8), where the gas is flowing in eccentric orbit with e = 0.2. The gas outside the gap is in Keplerian circular orbit. It is evident that the line profiles are asymmetric. For comparison, we display the symmetric double-peaked line profiles (dashed lines) emerging from a planet-free disk as well.