Jack Sock's win over Thiem leaves us wondering about their ceilings

Coming into the second-round match between Dominic Thiem and Jack Sock in Paris on Wednesday, you might have thought that the Austrian would be the hungry competitor, while the American would be the guy with one eye on the SORTIE door.

Thiem is currently seventh in the race to qualify for the eight-man field at the ATP World Tour Finals in London. He could have clinched a spot by reaching the final in Paris; even failing that, merely holding his seed and reaching the quarters would have helped his cause. Presumably, Thiem should have felt a sense of motivation after watching Marin Cilic, the player just behind him in that race, keep his hopes alive by beating Ivo Karlovic earlier in the day.

Sock, on the other hand, is currently 23rd in the chase; 15 players would have to injure themselves simultaneously for him to have a chance to play in London. Starting at the U.S. Open, he has had a good run of results—Round of 16 at Flushing Meadows, quarterfinals at the Shanghai Masters, final in Stockholm. Because of that success, though, Sock has played a lot of late-season tennis. Paris is his last event of 2016, and I’m guessing that 11 months on tour and three weeks on the European indoor circuit have been more than enough. Plus, going out to Thiem, a player he had lost to in both of their previous meetings, would hardly have been a disgrace.

Yet it was Sock who stormed out of the gate against Thiem, took him out of his game early and rolled to a 6-2, 6-4 victory in just 55 minutes. Sock hit 30 winners to Thiem’s 12, committed just 10 errors, made 80 percent of his first serves, won 91 percent of his first-serve points and was three for three on break points. It was so one-sided that when they shook hands, it looked like Sock asked Thiem if something was wrong. Thiem shook his head and smiled.

It’s true that Thiem has had his share of injuries this season; he retired from his match against Juan Martin del Potro at the U.S. Open and withdrew from Shanghai. At this point, though, the issue for him is probably as much mental as it is physical. Thiem has played 27 tournaments in 2016, the most of any player in the Top 20; Novak Djokovic and Andy Murray, by comparison, have played 17 each. All of those matches have taken their toll; after winning 55 of them through September, Thiem is just 2-4 over his last four events.

Thiem is 23, and has been widely touted as a future ATP star, Grand Slam champion and possibly No. 1. He has shown the makings of all three this season. In 2016, Thiem has won four titles on three surfaces, reached his first Slam semi—at Roland Garros—and has built a fan following, particularly among one-handed-backhand-loving traditionalists. But his overloaded schedule and late-season fade leave questions going into 2017. Is Thiem happy playing as many tournaments as possible and making as much money as possible, regardless of how he does at bigger events? This summer he skipped the Olympics in favor of a small ATP tournament. Thiem has talked a few times this year about cutting back on his schedule to focus on majors and Masters, the way elite players typically do. But we haven’t seen evidence of it yet.

Thiem’s loss to Sock points to another question: As fabulous as his one-handed backhand is, and looks, is it the right shot for today’s game? Since 2004, only Roger Federer and Stan Wawrinka have used it to win major titles. Few fans praise the two-handed backhand, but in today’s baseline wars it’s almost always going to be the more stable stroke over the long run. While Sock mostly uses his two-hander as a rally shot, he was able to boss Thiem around the court with his serve and forehand. One-handed backhands aren’t as useful for counter-punching as two-handers.

In that sense, this match also raised questions about Sock and his future. He’s just a year older than Thiem, but he hasn’t had the same level of success so far. His career-high ranking is 22, and he’s won one career title to Thiem’s seven. Sock certainly has the physical skills; few can belt a bigger forehand, and few are as quick around the court. Sock has worked to improve his weaknesses—return and backhand—in 2016, and right now he’s finishing the year on a higher note than Thiem. The next step for the American may simply be a matter of belief. He tends to play long, back-and-forth matches, where his game, confidence and concentration wax and wane from one set to the next. But in shredding Cilic at the U.S. Open, edging Alexander Zverev and Milos Raonic this fall, and running Thiem off the court in under an hour, Sock showed that is ceiling may be higher than we’ve so far believed.

With a little more from Sock, and a little less from Thiem, we could see these two players competing for important titles—rather than squaring off in end-of-season early-round matches—in the future.