How Jannik Sinner has changed his game ahead of the Australian Open

If it ain't broke, don't fix it. Good advice, you might think, especially for Jannik Sinner, who won two of the four majors in 2025 and was within one point of a third.

But when the man denying him the other two slams is Carlos Alcaraz, standing still is not an option. Alcaraz leads their head-to-head matchup 10-6, has won seven of their past nine meetings, and until Sinner beat him to win his first Wimbledon title last summer, Alcaraz had won five in a row.

For Sinner, something had to change. Immediately after losing to Alcaraz in the US Open final last year, he pinpointed what he needed: variety.

"I was very predictable today," he said in New York. "During this tournament, I didn't make one serve-volley, didn't use a lot of drop shots, and then you arrive to a point where you play against Carlos where you have to go out of the comfort zone. I'm going to aim to ... [try] to be a bit more unpredictable as a player because I think that's what I have to do ... to become a better tennis player."

Sinner is the two-time defending champion at the Australian Open, which began Sunday. Winning another would make him the only man other than Novak Djokovic, who did it twice, to claim three straight titles in the Open era. And yet, as Sinner begins his title defense, he knows that should he face Alcaraz in the final, he might need to offer something different.

The transition began quickly. Sinner won four of his five events after the US Open, including the ATP Tour Finals, relying largely on his usual style of outstanding baseline play, but also mixing things up more often, using drop shots more regularly and making more forays to the net.

According to Tennis Data Innovations, Sinner increased his variety -- how much a player varies his shot selection -- from 11.7 percent to 13.7 percent. That's still well below the Tour average of 19.1 percent, but represents an increase of 17 percent.

He also upped his use of slice from 3.6 percent to 4.2 percent, went from 1.5 percent of drop shots hit to 2 percent and, in the biggest bump of all, increased his net play from 3 percent to 4.3 percent.

Improving his net game was one of Sinner's main offseason targets. "We worked a lot on trying to make the transition to the net," Sinner said at Melbourne Park on Friday. "The serve, we changed a couple of things. But all small details. When you are at the top level, small details make the difference. I would say [in] the first matches, you try to get used to the match feeling again, and then after, you try to add something. We see how things go. We see what conditions we play in."

Variety comes easily for Alcaraz, who loves to go to the net when he can and who hit three drop shots in serving out for victory in Tokyo in his first ATP Tour event after the US Open.

Changing one's natural game is far from easy. Take Coco Gauff, who won her second Grand Slam title last year, but whose efforts to change her fragile second serve remain very much a work in progress.

Ivan Lendl worked tirelessly to improve his net game in a bid to win Wimbledon in the 1980s, even skipping the French Open, where he had won three times. It didn't work. Andy Murray, with the help of Lendl as his coach, added more power and aggression to his natural game, but it took time to pay off. Jack Draper was a natural counter-puncher (someone who is most comfortable turning defense into attack) because, as he has explained, he was short as a child. It took him time to become more aggressive.

It can also be dangerous to focus too much on one person. Roger Federer admitted he had to change his game to beat Rafael Nadal. It was only years later when he also made other changes, including using a bigger-headed racket, that he found the secret, winning seven of their last eight battles.