Primoš Roglic (Jumbo-Visma) admitted that he and his teammates are still using the nutritional supplement ketones this season.

The Slovenian's comments came in response to questions at a press conference immediately after finishing second in the summit finish of stage 17 of the Tour de France's Col de Rose on Wednesday.

Roglic's 15-second lead over Pogachar, combined with the time bonus given to second place, increased his overall advantage from 40 seconds to 57 seconds.

As a result of the time improvement and Pogachar's struggles, Roglic's options for the overall win four days later have leveled out, but Thursday's complicated final stage in the Alps may hold some important surprises.

The supplement "ketones," mentioned at the press conference, is believed to improve recovery in endurance athletes. Jumbo Visma coach Richard Plagge admitted in a report published in De Telegraaf last July that his athletes use the supplement.

Asked about the team's ongoing use of the supplement, Roglic said, "I can't say anything about [its] real benefits, because it's hard to feel. It's the end of the Tour, everybody is tired and we want to do the best we possibly can. We're just working hard towards it."

As for the battle for the summit finish, Roglic managed to avoid contact with stage winner Miguel Angel Lopez (Astana) when the Colombian made his final attack with 3.5km remaining.

The Jumbo-Visma duo then dropped Pogachar as Lopez moved ahead in the shadow of teammate Sepp Cusu.

Asked if he thought the GC battle was over, Roglic said, "No, I don't think so. But we have one less hard stage. This climb is incomparable and I am happy that this one is over."

Thanks to the high speed of the Bahrain McLaren, some of Roglic's usual support team, George Bennett, Wout Van Aert, and Robert Gesink, dropped out after the 21km climb. He and Lopez left the front, pulling Roglic away from Pogachar and Roglic himself from the same Slovenian rider.

Asked about Kuss' complicated role of first going on the attack, then shadowing Lopez, and then dropping back for Lopez, Roglic revealed that he had had a few conversations with the American just before. But on the other hand, I saw that the others were struggling, and I still had one rider who could help me. On this climb, every meter counts, and every little bit of support is important."

Although Roglic's time gap to Pogachar continues to be important for the remainder of the Tour de France, Roglic said that he is increasingly happy with his time gap to the Slovenian, but that "time is never enough."

"When you get something, you want more. I was happy with my position, but now I'm even more satisfied."

He said.

Meanwhile, as the Tour neared its end and Roglic's victory became more and more certain, the roadsides were filled with Slovenian supporters.

"The last few days have been crazy," Roglic said. 'You see a lot of Slovenian flags, especially in the last week, and it gives us something special. I hope they are proud of us."