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Former World Rally champion Sainz had already lost over an hour on Thursday following navigational errors and electrical problems.
The Spaniard had dropped from first to sixth in the standings.
Al-Attiyah had lost over 20 minutes to leader Nani Roma, but was still very much in contention for victory and in second place overall.
However, both men have been hit with one-hour penalties for missing one of the waypoints on their way to the control points.
The penalty has dropped Sainz to eighth place in the standings, nearly two hours behind Roma. Al-Attiyah is now fifth, one hour and 26 minutes off the lead.
Local Federico Villagra was also given a one-hour penalty that dropped him from eighth to 12th.
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