Is world No. 5 Alexander Zverev playing too much?

UPDATE: Alexander Zverev lost his opening-round match in Stuttgart, to Dustin Brown, 6-4, 6-7 (3), 6-3. Watch the match-point highlight above.

It appears that two-time French Open finalist Dominic Thiem is being challenged for his title as the ATP Tour’s workhorse by the player right behind him in the rankings.

As he gets ready to compete in his home event in Stuttgart on grass, Alexander Zverev will be playing his 12th consecutive tournament, in a run that has had more lows than highs. But will such an intense schedule serve him well in the long run, or will he be drained by the time the year’s last two majors—Wimbledon and the US Open—roll around?

While Zverev has yet to make his much-expected breakthrough at one of the Grand Slams, he has traditionally been one of the more consistent performers at the other events on the calendar, having won 10 titles before this year in a 26-month timespan. Among those were three Masters 1000 victories in Rome, Canada and Madrid; and his most important triumph to date, at last year’s ATP Finals, when he defeated Roger Federer and Novak Djokovic in consecutive matches.

Optimism was high going into 2019, and after another strong showing at the Hopman Cup, he was expected to challenge for the Australian Open title. He did manage to make it through to the fourth round for the first time, but fell to Milos Raonic. Zverev went from there to the Davis Cup qualifiers, winning both his rubbers against an overmatched Hungary squad, but was forced out of a string of indoor events due to injury and illness. When he did return to the tour in Acapulco, the German advanced to his first final of the year, losing to Nick Kyrgios at the ATP 500-level event.

In retrospect, it could be argued that he returned to action too soon as he lost early at the year’s first two Masters events in Indian Wells and Miami. The transition to clay wasn’t exactly smooth, either: Taking a wild card into the 250-level event in Marrakech, Morocco, Zverev—the only member of the world's Top 10 at the tournament—lost in the round of 16 to 60th-ranked Jaume Munar.

From there, Zverev went 4-5 over his next five events, as he failed to defend his titles in Munich and Rome. At the Geneva Open, still seeking match play and confidence the week before Roland Garros, the 22-year-old won the tournament for his first title of the year, eking out a third-set tiebreak victory against Nicolas Jarry in the final—a reversal of their earlier match this year in Barcelona.

In two of his first three matches in Paris, Zverev fought through five-setters against John Millman and Dusan Lajovic. In the fourth round, he defeated Fabio Fognini for one of his best wins of the year. World No. 1 Novak Djokovic stopped his charge in the quarterfinals without much difficulty.

Now comes Stuttgart, where the German will face one of the closest players to a grass-court specialist on the tour in countryman Dustin Brown. It’s a tough task for anyone, but should he pass this test, it will be a good measuring stick of the status of his confidence and game. Reuniting with him there will also be his coach, Ivan Lendl, the Hall of Famer who won 106 matches and 15 tournaments in 1982, and knows about a heavy schedule. Lendl learned about pacing to put himself in a better position to win majors as he finally captured his first in 1984 at 24.

Zverev is a couple of years younger than that now, and most observers of the game would agree that Grand Slam titles are in his future. Though he has been active for months now, he hasn’t had many deep runs at an event, which has preserved his legs somewhat, and his last two tournaments have been his best of 2019. Zverev and his team have to make sure he’s peaking at the right time and, despite his youth, take a break from the schedule, which could be crucial in determining his fortunes at the last two majors of the year.