Mirra or Mensik: Which young gun will have the best 2025 season?

As we make our way toward the 2025 season—which begins Friday, December 27 with the United Cup—our writers and editors tackle the most important questions of the new year.

Fourth question: Which young gun will make a major breakthrough next season?

Scroll down past this article to read more Burning Questions on 2025.

FRANZISKA BRUELLS: At the age of just 17, German Justin Engel won his first match at ATP level in October 2024, making him the youngest player to win a match at this level since Carlos Alcaraz in Rio de Janeiro in 2020. At the same time, he was the youngest professional in his class of 2007 to win a match on the men's tour.

The extent of his success was clear to see in the following weeks: He was invited to the Ultimate Tennis Showdown (UTS) in Frankfurt as a alternate player, where he trained with Dominic Thiem and Jan-Lennard Struff, among others. This was followed by the big announcement that the 17-year-old will be supported by former professional Philipp Kohlschreiber as a coach in future, will serve for TC Großhesselohe in the Tennis Channel Bundesliga from 2025 and is under contract with the sports marketing agency ‘Sportfive’.

Maybe I need to become a bit older. I think I'm already doing almost everything right. There's not much missing at the top. It's just mental, because you don't win most matches because you're the better player, but because you're mentally stronger than your opponent. Justin Engel

The basis for Engel has been laid. However, it was already there in terms of play: A cracking forehand that is a little like Alexander Zverev's, a solid baseline game, a hammer service and a good dose of self-confidence, which Engel can put to good use on the professional tour. What is he still missing to play at the very top? ‘Maybe I need to become a bit older. I think I'm already doing almost everything right. There's not much missing at the top. It's just mental, because you don't win most matches because you're the better player, but because you're mentally stronger than your opponent,’ said the 17-year-old himself in an interview with Tennis Channel.

Even though Engel is often compared to stars like Alcaraz and Zverev, one thing is very important to him: ‘I will always stay grounded.’ So he has the right professional qualities, now he just needs to keep up mentally with his much older rivals to really take off in 2025.

JON LEVEY: From an accomplishments standpoint, it’s difficult to imagine any player matching Coco Gauff when it comes to ranking, wins and big titles. Yes, she’s still only 20. But since she’ll turn 21 during the season, and is already firmly established, let’s take “best” to mean biggest leap forward. For that, I’m picking Jakub Mensik.

The ATP’s 2024 Newcomer of the Year won’t sneak up on anybody. The 19 year-old Czech has already cracked the top 50, scalped Top 10 players such as Andrey Rublev and Grigor Dimitrov, and earned a spot in the Nitto Next Gen ATP Finals. Standing 6’4” Mensik possesses ample firepower, but his determination has proven just as impressive.

Exhibit A was this past US Open. After disposing of Félix Auger-Aliassime in the first round in straight sets, Mensik dropped the first two sets to Aussie Tristan Schoolkate in steamy conditions. It would’ve been very easy for the then 18 year-old to call it a tournament. But he battled back, saved a match point in the fourth set, and completed the comeback in a fifth-set tiebreaker. He lost his next match, but it wasn’t for a lack of effort—it also took five sets. No wonder his nickname is the Menimal.

It's probably still too soon for Mensik to be a consistent Grand Slam threat, but grabbing a Tour title and climbing inside the Top 20 by the end of 2025 are well within his grasp

STEPHANIE LIVAUDAIS: The ATP’s Newcomer of the Year, Jakub Mensik proved that when he catches fire he can beat anyone. Look no further than Doha, where he defeated Andy Murray, Andrey Rublev and Gael Monfils on the way to his first ATP final, or to Shanghai where once again toppled Rublev and took down Grigor Dimitrov en route to his first ATP Masters 1000 quarterfinal. The 19-year-old Czech’s slow and steady progress shows no sign of slowing down, and he finished the year with a new career-high No. 48 ranking.

On the WTA side, Mirra Andreeva is poised to continue her rapid rise up the rankings. At 17 years old, she’s already broken through to the Top 20 and reached a Grand Slam semifinal, and she’s still taking aim at many of Martina Hingis’ “youngest since” records.

She added Spanish former No. 2 Conchita Martinez to her coaching team this year, and their partnership continues to bear fruit with Andreeva also finishing the year having won her first WTA title in Iasi and reaching another final in Ningbo.

Stay tuned for Friday's question: Which American woman will have a better season: Jessica Pegula or Coco Gauff?