Preview: Wawrinka vs. Federer In Australian Open SF

Much like their tennis careers have evolved over the years, so, too, has Roger Federer and Stan Wawrinka's friendship. Years ago, Wawrinka would frequently ask his compatriot for tips on how to play certain guys. Federer would kindly oblige, and Wawrinka would execute the game plans that Federer shared.

“That showed me that he's a great player, that he's got a mind of somebody who understands what I'm trying to explain to him,” Federer said after his Australian Open quarter-final win. “Some players, you tell them something, they've just got no clue what to do, what it means. Stan had that early on, so I think he was a great learner.”

Years passed, Federer kept hauling titles, but Wawrinka also improved. Eventually, around 2011, Federer's phone rang less and less.

“Then the day came where he didn't call me so much any more... I also felt like I didn't [need to] tell him any more, because he created his knowledge, his base, had his team. Only from time to time would I give him advice if he asked me. Otherwise I was happy that he was able to let go and go on his own path,” Federer said.

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Wawrinka did well on his own, eventually winning his first ATP World Tour Masters 1000 title at the 2014 Monte-Carlo Rolex Masters and three Grand Slam crowns, including the 2014 Australian Open. But the frequent communication between the two underlines how well they know each other and their games as they prepare to face off in Thursday's Australian Open semi-final.

Of the eight players who were in the quarter-finals, Federer said, only Rafael Nadal's knowledge of Federer's game could match Wawrinka's. “Stan and I practised so much together. With Rafa, I only practised once in my life, whereas with Stan, I can't even keep count anymore,” Federer said.

🤝🤜🤛 @rogerfederer @AustralianOpen pic.twitter.com/JhkvH5LsVr

— Stanislas Wawrinka (@stanwawrinka) January 18, 2017

Thursday's last-four match-up will mark their 22^nd FedEx ATP Head2Head meeting, a series Federer has dominated, winning 18 of the 21 contests. His record against Wawrinka is even more impressive on hard courts. There, Federer is a perfect 13-0 has won 28 of the 32 sets.

Federer, who's trying to reach his sixth Australian Open final, beat Wawrinka the last time they played on hard courts at a Grand Slam, a straight-set win in the 2015 US Open semi-finals. “He was playing way better than me, moving really well, really aggressive from the court,” Wawrinka said after his Australian Open quarter-final win.

Australian Open Final Appearances In Open Era

But, unless you haven't been paying attention to tennis during the past four years, you won't count out Wawrinka during a big match. The 31-year-old right-hander has never beaten a World No. 1 outside of a Grand Slam final, losing all 20 times. But in Grand Slam finals, he's a perfect 3-0 against World No. 1s.

“I'm more confident with myself. When I step on the court, doesn't matter who I play, I know what I have to do if I want to win,” Wawrinka said.

He will try to reach his second Australian Open final and his fourth Grand Slam final. Wawrinka will also look to extend his 12-match Grand Slam winning streak, a career best that dates back to his US Open title last September.

He has looked focused in Melbourne. Wawrinka has won all five tie-breaks he's played, and he converted all three break points during his quarter-final win against Jo-Wilfried Tsonga. “Against Roger, it's always special because he's so good. He's the best player of all time. He has an answer for everything. But I managed to beat him in a Grand Slam, so we'll see,” Wawrinka said, noting his 2015 Roland Garros quarter-final victory.

Their sharing of advice hasn't been a one-way conversation, either, Federer admitted. “Of course, I have,” he said when asked if he's questioned Wawrinka about players.

But, like their rivalry, Federer has led most of the conversations, and he'll try to lead Wawrinka on the court once more to reach his 28^th Grand Slam final. “We always used to talk to one another, naturally in Davis Cup, because then you were on the same team, you would talk about players. It has happened,” Federer said. “But it has been 95 per cent of me giving him advice.”

Grand Slam Finals Reached All-Time