In a major surprise, De Mevius prevailed by 1:44s on the 414km special between AlUla and Al Henakiyah and hence leads the event by the same margin, given the Prologue times merely determined start order selections for Stage 1 this year.
Sainz set off in the middle of the pack after mistakes in his Audi RS Q e-tron in the Prologue but, despite picking up three punctures, is now in a strong position.
Punctures did, however, wreak havoc on major rivals such as Nasser Al-Attiyah, who is 23rd after ceding more than 20 minutes.
Prologue winner Mattias Ekstrom had been fastest all the way to the Kilometre 225 waypoint on Stage 1 until he lost about eight minutes and gave up the lead to fellow Team Audi Sport driver Sainz.
The Spaniard, however, sat in top spot only at the Kilometre 281 waypoint, after which de Mevius nosed ahead in his Overdrive Racing Toyota entry.
Giniel De Villiers took third at 9:18s off the pace in his Toyota Gazoo Racing Hilux, ahead of Vaidotas Zala (X-Raid Arijus JCW) and Romain Dumas (Rebellion Toyota Hilux).
Ekstrom slipped to 10th, 14:20s away from top spot, with Sebastien Loeb (Bahrain Raid Xtreme) next of the big names in 19th at 22:47s off the pace.
Both Loeb and Prodrive Hunter stablemate Al-Attiyah were hit by punctures, the latter of whom copped two in the first 50km and had to tread carefully thereafter in the rocky terrain.
Al-Attiyah is 22nd at 24:47s from the lead while Audi’s Stephane Peterhansel is more than half an hour back in 26th.
There was also drama before the action got underway for the Cars, with the start of the special delayed when a spectator was involved in an incident with the Lionel Baud Overdrive Hilux and had to be airlifted to hospital.
An update from official timing read, “The start of the first car, which was scheduled for 10:15 am, has been moved to 11:15 am following an incident with a spectator about 200 metres into the special.
“The injured spectator has received medical care and been taken to the nearest hospital.”
Stage 2 from Al Henakiyah to Al Duwadimi starts in dunes but becomes a fast, 463km special.
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General classification: Cars Top 10
Pos | Num | Nat | Driver | Team | Time | Gap |
1 | 221 | BEL | GUILLAUME DE MEVIUS | OVERDRIVE RACING | 04H 35′ 59” | |
2 | 204 | ESP | CARLOS SAINZ | TEAM AUDI SPORT | 04H 37′ 43” | + 00H 01′ 44” |
3 | 209 | RSA | GINIEL DE VILLIERS | TOYOTA GAZOO RACING | 04H 45′ 17” | + 00H 09′ 18” |
4 | 214 | LTU | VAIDOTAS ZALA | X-RAID ARIJUS TEAM | 04H 46′ 41” | + 00H 10′ 42” |
5 | 231 | FRA | ROMAIN DUMAS | REBELLION RACING | 04H 48′ 17” | + 00H 12′ 18” |
6 | 206 | BRA | LUCAS MORAES | TOYOTA GAZOO RACING | 04H 49′ 24” | + 00H 13′ 25” |
7 | 243 | RSA | GUY DAVID BOTTERILL | TOYOTA GAZOO RACING | 04H 49′ 38” | + 00H 13′ 39” |
8 | 201 | KSA | YAZEED AL RAJHI | OVERDRIVE RACING | 04H 49′ 38” | + 00H 13′ 39” |
9 | 212 | FRA | MATHIEU SERRADORI | CENTURY RACING FACTORY TEAM | 04H 50′ 11” | + 00H 14′ 12” |
10 | 207 | SWE | MATTIAS EKSTRÖM | TEAM AUDI SPORT | 04H 50′ 19” | + 00H 14′ 20” |