Could Primož Roglič's time penalty for drafting lose him the Vuelta a España?

It's hard to know what would have hurt more – the 24% gradients upon which Primož Roglič turned himself inside-out to claw back a hefty 37 seconds on the Vuelta a España GC, or being told a short while later that said 37 seconds had been sliced nearly in half by a 20-second time penalty.

Given for drafting behind his team car after swapping to a low-geared bike for the brutal finale, it could be a sanction that will come back to haunt the Red Bull-Bora Hansgrohe rider long after his legs have recovered from Sunday's exertions.

Roglič, for his part, has remained outwardly pragmatic, saying on the rest day: "I don't like it but I can't change it".

Sunday's 15th stage of the Vuelta a España featured one of the hardest finishes seen in any Grand Tour for a long time. The overall stats of the hors-cat Cuitu Negru climb in northern Spain's Asturias mountain range (18.9km / 7.1%) simply don't do justice to how utterly barbaric the final 15 minutes of riding was.

These last three kilometres averaged between 12 and 14% and featured 24% ramps. We couldn't see much due to a thick blanket of cloud that enveloped the peak, but we could tell right enough how hard it was due to the facial contortions on display. No poker faces here.

Ironically, perhaps, one of the riders who gained the most on Sunday, Roglič, managed to keep one of the straightest faces as he distanced, pedal rev by excruciating pedal rev, the only man who appears to have any chance of keeping the red jersey off his shoulders come Sunday's Madrid finale – red jersey Ben O'Connor (Decathlon-AG2R La Mondiale).

You wonder exactly how straight Roglič's face will have been, though, when he was told of his time penalty. 

O'Connor took the lead on stage six after finishing solo 4:33 ahead of his nearest rival and taking the lead from Roglič. That appeared to be a calculated move on the part of the Slovenian, who was left 4:51 back in second place after that day. He has spent the past nine days decimating that lead (and perhaps regretting that calculated move), bringing O'Connor to what is now 1:03, but the Aussie is proving a tough nut to crack. Every second is hard won.

There are four clear GC days left, and given how quickly Roglič has recouped the time on O'Connor so far, the smart money would say that he will go on to retake the lead and win.

But 20 seconds can be a long time in cycling – an awfully long time. As we know, Grand Tours have been won by less. They are 20 seconds that Roglič could yet come to rue.