Ricciardo had stated after Friday's practice sessions that he knew he had a top-10 car for qualifying beneath him after a number of changes were made to his AT04 following last weekend's United States GP.
But even he seemed stunned, particularly with his genuine pace in Q3 around the Autodromo Hermanos Rodriguez after earlier being helped through Q1 and Q2 by a tow from team-mate Yuki Tsunoda, who already knew he would start from the back of the grid after taking a raft of new power unit components.
“From lap one yesterday I felt good, and really all weekend I felt we had a car to figure well inside the top 10,” said Ricciardo.
“This morning (in final practice), we were still there – P9 – but honestly, I was not happy with my lap this morning. I knew we could show more than that.
“You never know in quali because obviously everyone turns it up but I was confident in myself that I could definitely get some more tenths out of the car.
“In Q1 and Q2, Yuki was great, gave me a tow just to obviously make sure we got into Q3, but then in Q3, I didn't have a tow and we still showed really good pace.
“So I think that's probably the coolest thing about today, that it wasn't ‘Oh, okay, they did it, but he gained a couple of tenths from a tow'.
“We had raw pace, and actually the last lap when I crossed the line I was pretty angry because I didn't improve. I was up in the first sector and then we slowly lost it through the lap, so I kind of threw that one away.
“But by the sounds of it, no one really improved at the end with a second set of new softs so maybe the track kind of fell away, so that made me feel a little bit better.”
From the second row of the grid for the first time since the 2021 Belgian GP, Ricciardo took additional pride from the fact he was just over two-tenths of a second off the pole time of Ferrari's Charles Leclerc.
“Obviously P4 is amazing, but then you see pole and it's two-tenths,” said Ricciardo. “It's not like Max (Verstappen) or someone is seven or eight-tenths down the road.
“The gap is just as cool as the position. We're really there, and who knows what it means for tomorrow, but I don't think today's a fluke. I really felt like we had strong pace.
“With the perfect lap, I went through it in my head last night, and I thought maybe we could be a P6 or P7 if everything goes well.
“So I definitely had confidence that we weren't just a P10 car – but P4 is pretty cool.”
Asked by Speedcafe how he felt about that, particularly given his long-term goal, Ricciardo replied: “Look, it's cool, but I'm ahead of a lot of people.
“It's just cool to be that far up the grid again. It's been a while.
“There's part of me which, for the next hour, wants to celebrate today because it's certainly a day that should be celebrated. For the team as well, you know, it's not often they qualify this far up the grid, especially this year.
“I also don't think this car is a P10 in the constructors' (championship) car. It's definitely been more competitive, and I'm just glad I got the most out of it.
“So for the next hour, we'll enjoy, but then we definitely focus on tomorrow and try to turn this into a big bag of points.”