Watching Tom Dumoulin mature over the final week of the Vuelta has been a fascinating exercise.
Each day, the Giant-Alpecin rider has become more confident and assured - first limiting his losses on the steep grades of the Asturias mountains earlier in the week, then reclaiming the red jersey in Wednesday's time trial.
On Stage 18, Dumoulin marked every attack like a seasoned campaigner; on Stage 19, he launched his own assaults to increase his lead from three to six seconds - a slender margin, but an important psychologiucal marker.
What will Stage 20 bring? The profile of the 175.8km stage from San Lorenzo de El Escorial to Cercedilla suggests Dumoulin should be able to retain his red jersey. While the course traverses four Category 1 climbs, none of these feature the steep grades so often present on Vuelta mountain stages - the terrain in which Dumoulin, at 6'1" and around 70kg, is least comfortable.
Neither does tomorrow's stage end at the top of a climb, with the ascent of Puerto de Cotos ending 17km from the stage finish. Instead, the peloton faces a 6.5km flat run along the plateau followed by a 7km descent - ample time for Dumoulin to make up any small time gaps that may appear on the final climb.
On paper and on the basis of this past week's performances, it looks like Dumoulin is set to claim the Vuelta tonight. Of course, nothing is assured.
The big Dutchman could physically or psychologically collapse tomorrow (although it's unlikely).
Astana could go on the attack from the gun and we could see Fabio Aru gain minutees (if he's still in the race).
Joaquim Rodriguez (Katusha) could go on a long-range suicide breakaway to try and gain a minute-and-a-half and finally claim a Grand Tour victory at the age of 36.
Anything could happen, but as things currently stand it's advantage Dumoulin. Make sure you tune in tonight to discover whether the Giant-Alpecin rider will become the first Dutch Grand Tour winner since Joop Zoetemelk won the Tour de France back in 1980.
As Zoetemel himself told Dutch broadcaster BNR earlier this week. "it's time for a new Dutch Vuelta winner".