Sainz leads by 4:31s of those who have made it to the fourth bivouac for the overnight stop on Stage 6, which spans two days.
The latter has progressed furthest on the Shubaytah special, to the fifth bivouac, although he is only one of three to have done so.
Tomorrow, drivers will complete the special but, for now, they have no access to timing and hence do not know exactly where they stand in the competition.
A day earlier, Sainz strategically slowed down on Stage 5 in order to enhance his position in the road order for Stage 6, and it paid dividends given he has been fastest at each waypoint he has reached thus far.
The battle for second on the 48-hour stage is being waged between Ekstrom and Prodrive Hunter pilot Sebastien Loeb (Bahrain Raid Xtreme), with the former 48 seconds ahead of the latter at Kilometre 398, the furthest to which most of the big guns have progressed.
Stage 5 winner Nasser Al-Attiyah (Nasser Racing), however, is sixth-quickest to Kilometre 398/Bivouac D in his Hunter, having been forced to open the road on a day when the Cars followed a different route to the Bikes and hence could not benefit from the tracks made by the two-wheelers.
In the virtual general then, with 149km to go, Sainz is first, from Ekstrom, then Al-Attiyah at 21:43s off the pace and Loeb 36:51s back.
Two big names, though, are out of contention.
Overdrive Racing's Al Rajhi hit a clump of camel grass which sent his Toyota Hilux into a barrel roll.
“After 51km, everything was okay on a very flat chott and we were at full speed when I hit something,” he recounted.
“The car did a barrel roll and now it is damaged.”
Stephane Peterhansel has only made it to Bivouac C after a litany of dramas for his Audi RS Q e-tron which has caused him to haemorrhage two-and-a-half hours relative to Sainz already.
‘Mr Dakar' said, while stopped to repair a puncture, “We had a puncture and the hydraulic jack system started playing up.
“We don't have a hand jack so we don't know how we're going to change the wheel.
“With the damage to the hydraulic system, I've lost the power steering and I don't know how we're going to manage to pull through.”
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