But the British rider still faced a five-minute deficit to Honda rider Benavides heading into Friday's decisive stage, and faced the added difficulty of having to make up the time while being first in the running order, making navigation that much harder.
Sunderland finally finished almost 16 minutes behind Benavides after missing a waypoint early in the Yanbu-Jeddah test, leaving him third overall behind Ricky Brabec.
"I did my best job, I cannot be so disappointed," said Sunderland. "I tried so hard, and it started off well, but I couldn’t find one waypoint in the dunes, I was searching there for 10 minutes.
"But it’s like that – when you push the speed, the navigation goes down because it’s a fine balance. I knew today I had a big task ahead of me to open and finish in front of Ricky, and I tried my best and it was impossible.
"I’m super-happy, I gave my best and I was the third-best [rider]. The best man wins in the end and today it wasn’t us."
#47 Monster Energy Honda Team: Kevin Benavides, #5 Red Bull KTM Factory Racing: Sam Sunderland
Photo by: A.S.O.
Sunderland described this year's Dakar as the "toughest" event he's ever contested, noting how close the top 10 riders were in the overall standings for most of the rally.
"The pace this year was incredibly high and the guys opening the route were doing a great job, not losing so much time after the first days," he said.
"Really tough race, the toughest race I ever did. I’m really tired in my head and body, and I’m happy to have finished. Really long stages, dunes, stones, river beds, mountains… everything you can imagine. But it should be like that, I guess."
Fourth "above expectations" for rookie Sanders
Second-best of the KTM contingent was Australian rider Daniel Sanders, who concluded his maiden Dakar in fourth place - coming within one position of matching his compatriot Toby Price's third-place finish in his first appearance in 2015.
#21 KTM Factory Team: Daniel Sanders
Photo by: A.S.O.
Sanders, who scored a best finish of second on Stage 4, ended up within 40 minutes of Benavides' winning time at the end of the rally.
"It was a pretty perfect Dakar for me," said Sanders. "I was just learning every day and gaining as much experience as possible, it was really good.
"To come away with fourth overall and first rookie is really cool and above expectations for me. I've only been on the rally bike for four months, so I can't thank KTM enough and Jordi Viladoms [team manager] for coaching me. Can't wait for the next one."
Price himself was firmly in the hunt for victory when he crashed out during Tuesday's ninth stage, while Matthias Walkner was a distant ninth overall following early clutch trouble.