Upper panels: observed–calculated (O−C) times and residual plots for transit timings of K2-19b (top) and K2-19c (middle panel). O−C values were computed by subtracting a linear ephemeris from each timing measurement (black dots), taken from K2 data and from ground-based follow-up by Narita et al. (2015). Open blue circles indicate the best fitting model found by TRADES; the lower subpanels indicate the residuals of the TRADES-model. Bottom panel: radial velocity measurements from FIES (red circles), HARPS-N (green squares), and HARPS-S (black triangles), as well as the best fitting model from TRADES (blue open circles). The grey dotted line shows the TRADES RV model of both planets across the observation time window. Residuals against the model are shown in the lower subpanel.