The Colombian leader of Ineos Grenadiers lost over a minute to race leader Primož Roglič (Jumbo-Visma) as well as Enric Mas (Movistar), who finished second and third on the stage respectively behind breakaway winner Damiano Caruso (Bahrain Victorious).
Ineos Grenadiers looked like they had a plan on the earlier climbs of the stage as they set a vicious pace, ripping the peloton to pieces, but as they hit the closing stages they then turned their attention to attacking with their leaders.
However, it was clear that both Bernal and Richard Carapaz were struggling with the pace of the attacks.
Speaking after the stage, Bernal said: "I actually felt pretty good, but I was not able to handle the changes of pace,
"I could keep my pace, and Adam tried to help me, but I told him to do his own race because I knew I'd get to the finish fine, and that proved to be the best thing to do."
Yates did finish almost 30 seconds in front of Bernal but also lost a good chunk of time to Roglič and Mas after the Brit had tried multiple powerful attacks earlier in the climb.
"It was a crazy fast race in the first hour, then our idea was to push hard on the long climb and stretch things out on the last one as well." Bernal continued.
"That was the plan, but there were other riders who were very strong. So, we have to turn the page on that chapter and move on."
Bernal lost 1-05 to Roglič with Yates losing 39 seconds to the Slovenian. Carapaz, who was Ineos' third GC option lost a whopping 8-03 to the red jersey, seeing his overall challenge come crashing down.
Bernal added immediately after the race that he had no idea what the new strategy would be to beat Roglič: "[I have] no idea what the strategy would be, or where we are on GC. But we'll have to look at all of that and then decide where we go from here."
After the rest day, stage 10 is another largely flat stage but with a very tough climb towards the end followed by a descent to the line in Rincón de la Victoria after 189km.
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