Sainz holds a lead of just over 20 minutes over Loeb following Tuesday's 417km test between Ha'il and Al-'Ula, making him the favourite for overall victory with just three stages to run in the 46th edition of the rally-raid.
However, Loeb has arguably been quicker of the two on outright pace in the second half of the rally, winning three of the last four stages in his Prodrive Hunter. The Frenchman could have made it four wins on trot had it not been for navigational problems at the end of Monday's Stage 8.
Despite the closing margin, Richards conceded: "It will be a very difficult fight. Carlos [Sainz] is very experienced, he's been doing this for many years, but it's more for Carlos to lose now because Carlos will automatically win.
"I'm sure everyone will believe that, so tell Carlos, 'You have to take it [the car] to the end now, you're going to win it'."
Two-time Dakar winner Sainz is one of the oldest drivers on the 2024 Dakar at the age of 61, but has belied his age in the Audi RS Q e-tron to lead this year's event with three stages to run.
Richards was impressed by Sainz's performance this year, saying: "I'm amazed. Most of the guys who are 61 [years old] are going to retire, and I'm ten years older than him, and I should be retiring too, but I'm not going to retire until we win Dakar."
Asked what his strategy will be, especially after Loeb was left without an ally in Nasser Al-Attiyah following his withdrawal on Tuesday, Sainz said: "The strategy is not going to change because Sebastien [Loeb] is pushing very hard, he's going flat out, and so are we, logically, because otherwise, he'll eat up the ground.
"However, there are still three stages to go and we must not let our guard down, we have to keep going in the same way.
"We're going to start second [tomorrow], and we'll try to go as fast as possible. Tomorrow night we'll think about the day after tomorrow. [Mattias Ekstrom and Stephane Peterhansel] are far away, but tomorrow shouldn't be a special with big punctures.
"It's clear that we have to get through tomorrow, and we'll think about the past. That stage decided last year's Dakar and this year it's going to be tough. The punctures are still the same and don't depend at all on the tyre."
Loeb made up over four minutes on Sainz with his fourth stage victory of 2024 on Tuesday, having also stopped Stage 4 prior to his recent run of successes in the middle part of the marathon.
But the nine-time World Rally champion conceded that overhauling Sainz's 20-minute lead on pace alone will be tricky, meaning he will have to rely on some misfortune hitting the Audi driver in order to claim a maiden overall victory in Dakar.
"We need] to push, good navigation, and pushing is the only thing we can do," he said. "We can't think about what the others are doing, [we must] do our job, making up [the gap to Carlos Sainz] just by pace will be difficult.
"This is life, of course, and it would be nice to have another car close to me, especially these next few days, which will be long and hard [stages] with rocks, but I will try to do it myself."
