Maglia rosa Bernal was in a strong position on the penultimate day of racing, heading into the stage with more than two minutes on Bahrain Victorious rider Caruso.
But on the brutal 164km stage from Verbania to Valle Spluga-Alpe Motta, the Ineos Grenadiers leader found himself on the back foot, after Caruso launched an unexpected attack on the descent from the San Bernadino climb.
Caruso and his team-mate Pello Bilbao extended the gap to almost a minute on the second climb of the day, forcing Ineos to take action to minimise time losses.
Speaking after the stage, Colombian star Bernal said: “I had good legs and I knew I had teammates around me but when Caruso attacked, with his advantage increasing, I admit I was worried.
“It’s not the best to have the second rider on GC a minute in front of you. I still had three team-mates so I tried to use them and then arrive as fresh as possible on the last climb for tomorrow. We did well, we managed the situation well, but of course it’s difficult to manage the situation.”
On the descent from the San Bernadino with around 50km left to race, Team DSM were able to get clear of the peloton for their leader Romain Bardet, with Caruso and Bilbao bridging across shortly after.
The GC contenders then linked up with the remains of the day’s breakaway to work together, extending their advantage to 50 seconds on the Splügenpass.
Bernal was forced to burn his lead-out riders to close the gap, with Jonathan Castroviejo and Daniel Martínez putting in commendable efforts to minimise the losses.
By the finish, Caruso was along to win the stage but Bernal had been strong enough to close the gap down to just 24 seconds, which leaves him with a 1-59 advantage heading into the final 30km time trial in Milan.
Bernal said: “I’m satisfied with the result. I think we managed the situation well. Finally we had two minutes advantage for tomorrow’s time trial, so I think we’re in a good position.”
“Now I am confident for tomorrow's last stage, I have a two minute lead in the GC and I will give everything in the time trial."
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