By Martyn Herman
(Reuters) - Older brothers do not usually take too kindly to being offered advice by younger siblings but Germany's Mischa Zverev listened to 19-year-old Alexander and it helped turn his career around.
Until a few weeks ago the only Zverev being spoken about in glowing terms was the younger version, whose swashbuckling game has already seen him tipped as a future grand slam champion.
But last month in Melbourne the 29-year-old Mischa burst from the shadows to fell world number one Andy Murray at the Australian Open with a serve-and-volley style that went out of fashion with flares.
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Up to a career-high 35 in the rankings, still 13 places below his high-flying brother, Zverev has also forced his way back into Germany's Davis Cup team which this week in Frankfurt against Belgium will feature two brothers for the first time.
Since his only other appearance, in 2009, the Moscow-born Zverev has been ravaged by injuries, but he said the rise of his kid brother helped give him have a new positive outlook.
"Call it naive maybe but (Alexander) has this young positive outlook, he just kept telling me to believe in good things," Zverev told Reuters after the draw on Thursday.
"He tells me 'look just stop confusing yourself with facts', just believe in yourself because dreams can come true, like we saw not so long ago in Melbourne. He has had faith in me.
"I like to think I've helped him too of course. Telling him about my experiences on Tour and in life."
Family pride can be a big motivator though and watching Alex grow from the "little kid" who tried to join in with his brother's practice sessions to the "next big thing" spurred him on to greater efforts.
"When he started to play really well a year or two ago I was really thrilled and excited and then it was up to me to get my ranking up and improve my tennis," he said.
"I had to catch up with him and maybe be part of the journey he is taking right now. It's an incredible thing."
After all the hard graft to turn his career around, Zverev, whose father played Davis Cup for the former Soviet Union, is determined not to be a one-hit wonder and only remembered as the man who produced one of the sport's biggest shocks.
"I really did enjoy the whole experience in Australia," he said. "Looking back on it, the off-season was very tough, but now I realize it was actually a lot of fun because it was part of such a great journey overall.
"It has sunk in now but tennis moves fast. Whatever happened last week south of the equator has to stay there.
"That's in the past already so hopefully I can take the confidence and all the positive experience I've got from that and take that into the whole of the 2017 season."
The only problem is his crafty net-rushing style and volleying skills will no longer be a secret weapon.
"Players will focus on me now and try to figure out my game a bit better," he said. "But I'll accept that and keep working. You never know what's going to happen in the next few weeks."
Germany's Davis Cup captain Michael Kohlmann said Zverev's style was good for tennis.
"We were missing that style," he said. "It was an unbelievable match against Murray and I think it's opened up tennis a bit. Hopefully he can continue his form."
(Reporting by Martyn Herman; Editing by Toby Davis)