The men's Grand Slams were dominated once again in 2018 by Roger Federer, Rafael Nadal and Novak Djokovic—but plenty of other players have also made meaningful strides toward the top of the game.
With the Big 3's greatness impossible to sustain infinitely, these next-in-line stars will look to step up at the Slams in 2019, starting with the fast-approaching Australian Open.
Here are five players who could be ripe for a breakthrough at the highest level this year:
1
At 21 years old, Zverev has won titles at every tier shy of the majors—including three ATP Masters 1000s and, this past November, the ATP Finals. The world No. 4 hasn't reached the same heights on the biggest stages and under the best-of-five format yet, but keep in mind: Federer was 21, too, when he won his first of 20 Slams and counting.