Shelton is the better player and the market is right to make him favourite, but the price assumes he cruises, and his opening round did not look like a cruise. Tallon Griekspoor took the first set 6-1 and dragged him into a third set tiebreak before Shelton finally pulled away in four. That is a lot of stress for a seed against someone who was not supposed to trouble him. Hurkacz brings a different problem. He does not need to break serve to stay in a match, because his own delivery keeps almost every set inside a couple of points. Against another heavy hitter that tends to mean tiebreaks, and tiebreaks are where favourites leak sets. He also came through Damir Dzumhur in four, dropping the second and then closing out 6-1 6-1, so the level is clearly there. Best of five works for the underdog on this line. Hurkacz does not have to win the match, he only has to take a couple of sets along the way. One strong serving day, one tiebreak that lands his way, and this is home. Shelton winning in three quick sets is a real outcome, and nobody should pretend otherwise. It just does not look like the most likely version of a match between two men who both hold serve for fun.