Simon Yates (Mitchelton-Scott) produced a phenomenal performance on the Stage 16 time trial to Rovereto limiting his loses to 1 minute 15 seconds from Tom Dumoulin (Team Sunweb). With four true stages remaining - Stage 21 being a processional stage to Rome - Yates seems to be in a commanding position to secure a maiden Giro d'Italia.
He judged his effort well, ensuring he lost equal time across the course rather than going too hard at the start then fading in the latter stages. On the reverse, Dumoulin will be disappointed with the lack of time regained on Yates in what he would have seen as his biggest chance for victory.
To add insult to injury, Dumoulin also missed out on a second time trial stage victory in the race. Rolling in third, the Dutchman conceded 22 seconds to race winner Rohan Dennis (BMC Racing) who produced a spectacular performance to secure the stage.
On the day, Dennis was unbeatable and thanks to Velon, we can gain a little insight into the numbers needed to ride with such dominance.
The Australian looked in control at all times, posting the fastest time at all three time splits, averaging 51.3kmh across the 34.2km stage, 0.3kmh faster than second placed Tony Martin (Katusha-Alpecin).
Over the final 5km, Dennis produced some big numbers to maintain his speed. For a total of 6 minutes and 2 seconds, the BMC man averaged 400W to keep an average speed of 50kmh. That saw Dennis produce 5.6W/kg to the finish.
This is impressive considering the efforts of Dennis earlier in the trial. The last 2km before the first intermediate sprint saw Dennis average 440W for 2 minutes 34 seconds which is around 6.1W/kg.
Added to Dennis's incredibly aerodynamic position, this power was clearly used efficiently enough to distance some of the world's best time trialists.
To put his effort into comparison, climber Domenico Pozzovivo (Bahrain-Merida) conceded 19 seconds over the same final 5km. That said, although he averaged 40W less, his watts per kilo figure was actually higher at 6.4W/kg.
This is clear evidence of the importance that aerodynamics play in the test against the clock and the advantage specialists get from having such a dialled-in position.
Behind the front runners, others also put in big efforts despite the race still containing three more mountain stages.
Despite the need to help Chris Froome over the days ahead, Team Sky's Vasil Kiryienka was clearly pushing for victory today. Although he finished 1 minute 4 seconds down, the Belorussian produced 410W on the first climb, 430W on the second and 410W for the third climb.
Chad Haga (Team Sunweb), another domestique with a big week ahead, also left a lot on the road. In the final 5km the American maintained 400W actually covering the distance 8 seconds quicker than Dennis.