Ernests Gulbis is known for a lot of things. He is known for being outspoken and controversial. He is known for being a bit of a headcase, unable to focus properly on tennis. And he is known for beating Roger Federer (at Rome in 2008) when he was just a teenager.

Expectations for Gulbis were astronomically high as soon as he burst on to the scene that week in Rome. Two weeks later, he followed it up with a quarterfinal appearance at the French Open. He had moved up in to the top 30 and was expected to be the next challenger to Federer and Rafael Nadal. Unfortunately for him, reality got in the way of his expectations. He could not play consistently well and was too focused on other things to play tennis properly, and his ranking slipped all the way outside the top 100.

Now, after six wasted years, Gulbis’ situation is eerily similar. He is finally back in the top 30, constantly raising his career-high ranking again. He just defeated Roger Federer for a second time. And, for the first time since that 2008 Roland Garros, he is in the quarterfinal of a Grand Slam once again.

So what is to stop history from repeating itself for Gulbis? What is different this time around? What makes us think that his extreme talent won’t take another six-year walkabout? Gulbis made headlines last week for seemingly sexist comments. He’s still quite brash and doesn’t mind speaking his opinion. He will say what’s on his mind without too much concern for the consequences. So why do we expect his attitude on the tennis court to change for the better?

The answer is that it already has. Gulbis is now making comments about living up to his talent and taking responsibility for being a professional tennis player and not just a talented individual who plays professional tennis as a hobby. Gulbis’ resurgence has not been the meteoric rise that happens with a new player bursting on to the scene. It has been slow, methodical, and an increase of consistency that shows a real dedication to devoting himself to the sport—both physically and mentally.

We are seeing Gulbis learn from mistakes in a way he didn’t do before. A few months ago, he was still having trouble serving out big matches. Now, nerves don’t seem to faze him much. While still fiery towards himself (and his racket) on court, he is much more cognizant of his opponent and situation. When he was forced to take a medical timeout before Federer’s service game in their match, he was apologetic towards Federer about this unavoidable breach of etiquette. He is treating the game of tennis like his life now, no longer like a toy.

Gulbis is 25 now. He is six years wiser and more experienced than when he first burst on to the scene. Back then, he was flying high, and everyone expected the world of him. Now, though, he is humbler and steadier. And he may just be ready to deliver the world.