Nairo Quintana has admitted he failed to hit the heights expected of himself in 2018 after disappointing performances at the Tour de France and Vuelta a Espana.

Quintana was backed to challenge for a third grand tour victory this year after focusing his preparations on the Tour.

However, the Colombian was well of the pace throughout the three weeks in France and had to settle for a top-10 finish – helped by victory on the Col de Portet on stage 17.

Quintana finished 14 minutes and 18 seconds behind eventual winner Geraint Thomas, and his fortunes did not improve in Spain.

Riding in support of Movistar team-mate Alejandro Valverde, Quintana ended in eighth position in the general classification, nearly seven minutes adrift of Simon Yates.

"I haven't fulfilled all my objectives this year, and if that doesn't work out, it seems like you've done nothing all season," he told reporters at Movistar's team meeting in Pamplona.

"But I wasn't missing in action, I was there, fighting away, sometimes better and sometimes worse. What's clear is that this was not my best year and not what we hoped for.

"I lacked that spark in the Tour and Vuelta. I had a crash in the Tour, which affected me, and I still have some lasting effects of that, but we were always thinking about the Tour.

"We overdid it, and in the Vuelta I was exhausted. I always wanted to be up there, but although the first part of the race went well, I faded away in the second."

Despite his disappointments, Quintana remains confident he can become a grand tour contender again, and completing the triple crown with a Tour title remains his number one goal.

"Next year we'll try and do it better, and it's clear that I'll be doing the Tour de France again," he added.

"That is what [team boss] Eusebio Unzue has told me will happen.

"We need to look at what we did in the past, when I got onto the podium in the Tour, and more or less repeat that strategy. That's the idea for 2019."