“It’s a logical response because guys return so much better and are able to neutralize the big serves better,” said Justin Gimelstob, who recently coached John Isner, the 6-foot-10 American who has one of the biggest and best serves in tennis. “The serve is the one stroke in this sport you completely control. Sampras, Becker, Goran, Isner, Kyrgios, Zverev are all big guys with incredible service motions and incredibly live arms who in big moments are willing to bet essentially on their ability to blow their fastball by a great fastball hitter.”
GIG also found that the average rally length on second-serve points dropped to four strokes in 2017 from five strokes in 2016, although that could also be related to faster playing conditions, more aggressive returning or other factors.
GIG’s data shows that the men are now hitting second serves closer to the lines on average, which is also true for the women. But while the average women’s second serve at the Australian Open increased to 137 kilometers per hour (85.1 miles per hour) in 2017 from 132 k.p.h. in 2013, the average speed of a men’s second serve is still at 150 k.p.h.
Still, some men have clearly cranked up the power. Kyrgios’s average second serve was 157 k.p.h. at the 2014 Australian Open; this year it was 182 k.p.h.
“It’s high percentage for me to go big under pressure,” Kyrgios said in Miami this year after losing a classic three-setter to Roger Federer that was full of second-serve risks. “Sometimes it comes off, and sometimes it doesn’t.”
It is not just the younger players who are re-engaging in swordplay. Sam Querrey, the American veteran who is having his finest season at age 30, began hitting more powerful second serves than usual in Shanghai this month.
“Sam threw it in, tried it, and it worked,” said Craig Boynton, Querrey’s coach. “My conversation with anybody that is going to do that, and I think Nick does it far and away more than anybody else, is what is your consistency rate? And what is the score line? When you are down 15-40 or 0-30 you are really rolling the dice, but if you are 30-0, 40-15 up and you want to throw a different wrinkle in, it’s a different equation.”
It is also a more favorable equation on a hard court or in an indoor tournament like the Paris Masters that begins Monday. Wherever it happens, a second-serve ace does seem to have a bigger psychological ripple effect than a first-serve ace. It sends a message that an opponent is unpredictable but also bold.
“Absolutely,” said Paul Annacone, who has coached Sampras and Federer. “When you’re helpless because of a first serve, it’s one thing but it’s another thing when all of the sudden you are playing Kyrgios and it’s 3-3 in the tiebreaker, which it was against Roger in Miami, and he hits a second-serve 131 miles per hour up the T that is unreturnable.
“To me, you either go, ‘He’s crazy.’ Or you think, ‘Now I’m not even getting a look at his second serve in big moments?’ That’s a huge impact. No. 1, you have to have confidence to do it. There’s a big difference between doing it out of desperation and doing it strategically. When Kyrgios does it, I don’t have a problem. People will go, ‘Oh, it’s a bailout.’ But he’s a great server. He believes he’s going to make that second serve, just like Pete did.”
Sampras, who won 14 Grand Slam singles titles, was undeniably one of the best servers in history, and there are highlight packages on You Tube devoted solely to his second-serve aces.
“In the 1999 Wimbledon final, he beat Andre Agassi and I remember going through the match afterwards, and I saw that Pete was serving almost 7 miles an hour faster on second serve against Andre than he had the whole tournament,” Annacone said. “So I asked Pete, and he said two things: one, ‘It’s Andre, so I had to.’ And two, ‘Because it’s my strength, and I can.’ ”
So why don’t more players routinely hit their second serves as hard as their first serves?
In 2014, FiveThirtyEight explored the question and determined that “nearly every player would be hurt, not helped by treating the second serve like a first,” because their double-fault count would get so high that it would end up hurting their second-serve winning percentage.
A more selective approach still feels — now as then — like the correct approach.
“My thinking with it is pretty simple,” said Ryan Harrison, an American currently ranked 46th.“I don’t pay attention to double faults as much as I do second-serve points won. I feel like if you’re getting the reward you should be trying to go after it. I’ve always been able to control mine, and keep the double faults down, so it made sense to keep going for it. If you’re double faulting eight times a match, and you are winning less than 50 percent of the points, then you need to re-evaluate.”
Heading into the tournament in Basel last week, the 25-year-old Harrison was on the cusp of re-evaluation: at 49 percent of second-serve points won in 2017 (50 percent for his career).
It is indeed a telltale statistic. As of Monday, the two men’s players with the best winning percentages by far on second-serve points were Rafael Nadal at 62 percent and Federer at 60 percent.
Nadal, at age 31, is back at No. 1 in the world rankings; Federer, at age 36, is at No. 2.
Neither is a serial risk-taker on second serves in part because their baseline games are so strong that they rarely need to be, although Annacone thinks Nadal would benefit from being bolder in some cases, including his four losses to Federer this year.
“I think Roger’s the best one-two punch server in the history of the game: using his serve to then get a forehand and Rafa is right there, as well,” Annacone said. “Even with second serves, Roger has enough creativity to find ways to open the court and then get a big forehand that he doesn’t feel, ‘I have to hit a line on a second serve otherwise I’m in trouble.’ ”
But some of those who do serve more dangerously are also in the top echelon in 2017. Kyrgios, who has ended his season early, is at 54.9 percent of second-serve points won, putting him 10th over all on tour.
Zverev, now ranked No. 5, is at 54.4 percent, putting him 13th.
They, not Federer and Nadal, will likely be setting the tone and the trends in the years to come.