Mischa Zverev knows his little brother better than anyone.

A decade older than Alexander, who is also known as Sascha, Mischa has served as part-sibling, part-parent throughout Alexander’s life and tennis career.

When Sascha was 6, Mischa took him along while he was playing satellite tournaments in Australia, hitting with him after his matches and letting him ride on his shoulders on the way home from the beach. Now the little brother is ranked No. 2 in the world, reached the French and U.S. Open finals, won an Olympic gold medal and is about to play in his seventh ATP Finals. He also won his seventh ATP Masters 1000 event last week at the Rolex Paris Masters.

He has had his off-court travails over the last several years, including now-settled charges of domestic abuse and an on-court outburst during a loss in 2022, for which he was fined and placed on probation by the ATP.

“I do know what I did, I do know what I didn’t do,” he said this spring before the charges were settled. “That’s, at the end of the day, what’s going to come out, and I have to trust in that.”

Zverev, 27, won the ATP Finals in 2018 with back-to-back wins over Roger Federer and Novak Djokovic, and then again in 2021 when he beat Daniil Medvedev in the final. The indoor tournament, which begins on Sunday in Turin, Italy, suits his style.

“There’s no wind, no sun, nothing to distract me too much,” Zverev said in September. “I like having to play at 100 percent from the first match on. And it helps to have past success at a tournament. That’s something you can keep in the back of your mind.”

Grigor Dimitrov has lost to Zverev in seven of their nine meetings, but beat him at the Miami Open in March.

“Sascha is a super complete player,” Dimitrov said. “I don’t think there’s too many people that can hang with him on the backhand cross. He’s also one of the most patient players out there, and you know that he will never give up.”

This season has been up and down for Zverev, especially at the majors. He upset Carlos Alcaraz to reach the Australian Open semifinals, but lost to Medvedev after being up two sets to love. He knocked Rafael Nadal out of his last French Open and reached the final, where he lost to Alcaraz after leading by two sets to one.

At Wimbledon, Zverev fractured his left tibia where it meets the knee, but still led Taylor Fritz by two sets to love in the round of 16 before losing. Before the U.S. Open, where he lost to Fritz in the quarterfinals, Zverev was diagnosed with pneumonia. He said he felt depleted for weeks afterward.

Zverev is keenly aware of his lack of a Grand Slam title. Soon after winning his Olympic gold in 2021, he lost to Dominic Thiem in the final of the U.S. Open, again after holding a two-sets-to-love lead. His brother acknowledged that his struggles were more mental than physical.

“It’s not his game, his groundstrokes, his forehand or backhand,” Mischa said. “The outcome is decided in his head. I don’t want to call it a mental problem or weakness. But the solution is there. There’s no secret. He has all the information. He just needs to take what he wants to take.”

Zverev said he believed that time was on his side and that he must remain optimistic.

“I’ve learned to enjoy the game of tennis, the defeats, the wins obviously,” he said. “When I was younger I was very anxious. I was like, ‘When is this going to happen, when am I going to win that?’ Now I just enjoy being here.”

When Zverev was 3 and started playing tennis, he said the family learned that he had Type 1 diabetes. His mother, Irina, was concerned about her son’s ability to lead an athletic life. It was Mischa who allayed her fears.

“I said, ‘Don’t worry, he’s going to be world No. 1, he’s going to be a Grand Slam champion,’” Mischa recalled telling his mother. And how did the big brother know that?

“Because special people have special tasks in life,” Mischa said. “And his task is to achieve all that and show everyone that it’s possible.”