Yates (Mitchelton-Scott) will join Team Sky's Chris Froome and Geraint Thomas in conquering the sport's biggest races in 2018 after he completes Sunday's largely processional final stage into Madrid.
Yates made his decisive move with 17km remaining in the brutal 97.3-kilometre Andorran stage, breaking the resolve of his nearest challenger Alejandro Valverde (Movistar) and effectively confirming his ascent to the title.
He eventually settled for third on the stage, 23 seconds behind Enric Mas (Quick-Step Floors), who pipped Astana's Miguel Angel Lopez in a sprint to the summit of Coll de La Gallina to move up to second place general classification, one minute and 46 seconds adrift.
"It’s still sinking in. I’m incredibly proud. I’m also incredibly proud of the team. They’ve carried me for these entire three weeks. It’s the first Grand Tour for the team. It’s just unbelievable," Yates said.
"Adam (Yates) was running out of legs (when he attacked in the penultimate climb) and I didn’t want to end up in a position where I could have been riding in the valley, that would have been the worst situation possible.
"I knew [Nairo] Quintana and [Miguel Angel] Lopez were up the road and Lopez had something to win so I figured maybe he could work with me. Sometimes attack is the best defence. In the last climb I was ok. I was at my limit. Mas and Lopez were riding incredible. I just tried to make my own rhythm. I gave everything I had and thankfully it was enough."
It was a different story for Valverde, however, with the veteran former champion clearly struggling up the final climb and ultimately dropping from second to fifth in the overall standings, four minutes and 28 seconds behind.
Valverde had failed to follow Yates when he attacked with 17km remaining, taking Mas with him as they sought to reel in the leading pair of Lopez and Nairo Quintana (Movistar).
"You have to accept defeats. When you win, awesome, and when you lose, it means the rivals were stronger than you," Valverde said.
"I was suffering a lot in the second ascent of Coll de Beixalis. I suffered from there and that was it. The team has been phenomenal during the whole of La Vuelta and Nairo (Quintana) proved today a good a teammate he is.
"Of course it hurts (to get down the podium) but you can’t ask for anything more when you’ve given it all you had. We take home the teams classification. I take the points classification and two stage wins."
Lopez and Mas ultimately went clear to contest the stage with Yates happy to remain in second place, as Quintana dropped back in a futile attempt to drag his Movistar teammate Valverde back into the reckoning.
"I looked at the video of Alejandro Valverde’s victory here in 2012 and I knew I had to come first in the last curve. I went full gas until the corner and then I just kept going until the line," Mas said.
"This is my second big victory after the stage at the Vuelta al Pais Vasco and I’m very happy with it. I’m also very happy with my second place on general (classification) although I’m a bit nervous not to crash and do anything stupid in Madrid.
"I’m a young 23-year-old kid enjoying myself. I’ve been dreaming of this for years. Today is about enjoying, tomorrow too. And I hope this won’t be the only time.
"I’m not the new Contador, I’m Enric Mas. I hope I can achieve half of his victories. I think it’s enough. I really like how he raced so if I can I’ll try to race like him sometimes."
La Vuelta a Espana concludes with the traditional final processional stage in Madrid, with coverage to begin from 2.00am AEST on SBS VICELAND, streaming online via the Cycling Central website and on Twitter.