Saudi Arabia booked an Asian Cup last-16 showdown with South Korea after a lively but goalless draw with Thailand on Thursday that clocked up four disallowed goals. It sets up a clash between two of the tournament favourites and a managerial face-off between two legends of the European game in Roberto Mancini and Jurgen Klinsmann. Mancini’s Saudi Arabia had already booked their place in the next round, as had Thailand, but Group F top spot was still up for grabs when they kicked off in Doha. Saudi Arabia, who won their opening two games, were undefeated in their last 12 matches against Thailan…