New Davis Cup captain Lleyton Hewitt has defended the often-maligned Bernard Tomic against critics of his laconic style, while admitting there is a "fine line" being walked at times by both the Australian singles No.1 and the more demonstrative and emotional No.2, Nick Kyrgios.
Hewitt, whose record-breaking cup-playing career ended last   September, will oversee the first-round tie against the US at Kooyong, starting on Friday. Tomic, ranked 21st, will start against world No.23 Jack Sock, while the in-form Kyrgios faces 11th-ranked John Isner on grass at Kooyong. 
Tomic's effort late in matches has been questioned several times, notably by John McEnroe during his 2012 US Open loss to Andy Roddick, and as recently as this year. Having controversially retired from his semi-final at the Sydney International, Tomic also raised eyebrows after a 7-6 (7-3), 6-1 fade-out against Rajeev Ram in Delray Beach this month.
"Bernie's had a couple of little niggles the last couple of weeks that not everyone knows about," said Hewitt, who has developed a strong relationship with the Queenslander after unhappy beginnings. "[Against Ram it] was probably a fine line, because I thought he played exceptionally well in the first set, and he wasn't quite able to get over the line, and then obviously lost his way early in the second.
"But that can happen to anyone, it's happened at times to me throughout my career and I guess it's [to do with] how he carries himself sometimes on the tennis court because he doesn't get as fired up as a lot of other people out there and now it's got to the stage where any time he loses, especially to a lower-ranked player, people think he's not giving 100 per cent.
"So it's just easy to hop on the bandwagon for some people now, but Bernie still goes out there and competes 100 per cent - every time I've seen him play, anyway. It's just about him doing it week in and week out now, and hopefully he's able to back up from playing in those big tournaments and have that motivation every week."
Tomic is through to the semi-finals of the Mexican Open in Acapulco after a 7-5, 7-5 win over Illya   Marchenko of Ukraine.
While Tomic has generated some unfortunate off-court headlines, the main issue for Kyrgios has been controlling his on-court emotions.
Hewitt said getting fired-up often helped the 20-year-old Canberran to play his best tennis; before winning his maiden ATP title in Marseille last week, Kyrgios - like Tomic - had been at his best on the bigger stages.
But is yelling at his entourage a good or bad thing? "It depends ... if you use it in a positive way afterwards and you're letting some steam out and then can get your focus back on the match. I've done it numerous times in my career and I was always able to pretty much turn it around, let out frustration and then get back on with the match. Andy Murray's a guy that does it as well. So it's natural but it's still got to be in a positive way. You can't keep letting it affect your tennis, I guess, and sort of let it drag on."
Asked, in general terms, what his 35-year-old self would advise the talented twentysomethings as they climb towards the top of a game in which he reigned as the youngest-ever No.1, Hewitt said a disciplined and dedicated preparation was "a massive key" to his ability to achieve so much, so early.
But these are different times, he also acknowledged, and Hewitt said Tomic and Kyrgios were contrasting characters whose individuality should be encouraged. "You still want them to be themselves, and the reason Nick's had so much success is because of his self-belief on the court, and how he goes about it, but it's just small fine-tuning here and there, and for them to mature as well, not only as tennis players, but as people.
"They're really in the spotlight with the way social media is these days, as well. There might have been things that have happened that possibly couldn't have been picked up maybe 20 years ago, purely because everyone has a phone or a recorder or whatever now. So there's things they've just got to work through, but I think both guys are on the right path, and I'm just one resource there that they can sort of tap into to give them the best possible opportunity to fulfil that potential."
Kyrgios set up a semi-final clash with Stan Wawrinka in Dubai in the early hours of Saturday (Australian time) with an impressive 6-4, 6-4 win over world No.7 Tomas Berdych. It was to be Kyrgios' first match against Wawrinka since last year's infamous sledging incident.
Tomorrow: Captain Hewitt, back to the future.