Top: observed minus calculated eclipse epochs for V893 Sco, using the best fit linear ephemerides. The filled and open symbols represent eclipses of this paper and of Mukai et al. (2009), respectively. The solid line is the best fit sine curve to the filled symbols. The dotted and dashed curves represent solutions for an eccentric orbit of an assumed third body with eccentricity e = 0.3 and e = 0.6, respectively (see Sect. 6.2). An empirical estimate for the error bars of the individual points is shown in the upper right corner. Bottom: observed minus calculated eclipse epochs using the final ephemerides described by Eq. (1).