The Colombian climber moved into pink with a dominant performance on Sunday's summit finish to Blockhaus, but says that he could struggle to stay in the lead with Thibaut Pinot (FDJ) and Tom Dumoulin (Team Sunweb) both within 30 seconds on GC.
"It’s obvious that I should lose some time tomorrow," Quintana said at a press conference on Monday's rest day.
"We’re facing a strong Tom Dumoulin, a talented specialist; also Thibaut Pinot, who rides well against the clock. They will surely do better on tomorrow’s course than me, though I hope not to lose too much time.
"I’d of course like to keep the maglia rosa, but we know it’ll be difficult. I wouldn’t dare to say how much time lost would make me happy. I’ll wait for tomorrow to see how I feel about my performance."
Watch: Giro d'Italia stage 10-15 preview
Asked what would be his strategy for the rest of the race, particularly in the mountainous final week in the Alps, Quintana insisted that he didn't want to look beyond Tuesday's time trial.
"Let’s see how we do on Tuesday and we’ll start building our race strategy immediately after that," he continued.
"I won’t comment anything about that strategy. However, what’s clear for us is that we will continue to make our moves on the terrain that favours us, and work as hard as we’ve done so far.”
Tuesday's stage sees the riders face a 39.8km time trial from Foligno to Montefalco, with a rolling course that should favour the GC contenders as much as the pure time triallists.
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