Rassie van der Dussen is standing and staring at Nasser Hussain in Port Elizabeth. van der Dussen has what cricketers call a "small-bag day". That's when you have already batted for the last time in the game and you'll not be bowling. You're at the ground purely because it is expected, but you have no real function. Most players use this time to do some extra fitness; Dean Elgar is doing laps of the outfield.

van der Dussen is not moving much at all. The previous night he moved a lot to Joe Root's fast offspin, his bat swinging across his front pad in panic. Root spun some and skidded others from around the wicket; van der Dussen was more victim than batsman. Such was the spectacle that now Hussain is on the square demonstrating for Sky the correct method to play this kind of bowling.

This kind of broadcasting is not exactly new. Sky have become masters of it, but SuperSport, Channel Nine, Ten Sports and Channel Five have all done it in the past. The difference in this case is that the most captivated viewer isn't a kid hoping to learn something about playing offspin from around the wicket, it is van der Dussen.

It's not unknown for players to watch clips of their techniques, but it's almost unheard of for them to be watching a Masterclass about themselves live. Most would worry about appearing to admit to flaws or weakness by doing so.

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"If there is something that Nasser said that could help me by 1%, I'd like to know what it is," van der Dussen said to me later.

If you looked around the field before day five at St George's Park, you'd see that players, coaches and commentators were in contact all over the place. Joe Root sought out former players on the ground, asking for their thoughts on bowling strategy. He spent more time intelligence-gathering than warming up.

Sam Curran talked to Surrey team-mate Gareth Batty.

Stuart Broad was in an on-field interview, mentioning how his former wicketkeeper Matt Prior was helping him with his lengths.

Over the course of the Test, Darren Gough, who has been on England's last four tours (three as commentator, once as coach) and is commentating for talkSPORT 2 now, talked to England coach Chris Silverwood, Root, Chris Woakes and Mark Wood about cricket matters.

Darren Gough, commentating on the match, had advice for Mark Wood on his lengths on the St George's Park pitch Getty Images

And SuperSport's Kevin Pietersen and Shaun Pollock were walking Faf du Plessis through tactics on playing spin.

There are paid coaches in team tracksuits, and there are unpaid consultants in their day clothes.

The line between commentator and/or coach has never been slimmer. Shane Warne is a global commentator and owns a small stake in Rajasthan Royals. Wasim Akram is director of cricket operations at Karachi Kings and does a lot of commentary. Both men are also fixtures at grounds around the world, transient mentors sharing secrets about their craft. Ravi Shastri was the biggest voice in Indian cricket before he took over as coach.

In Australia, Darren Lehmann was the national coach and, at the same time, a commentator on the Big Bash. Sitting next to him would often be Mark Waugh (then Australia selector) and Ricky Ponting (soon to be an Australia support coach). This season the Test captain, Tim Paine, has also been commentating at the BBL. And Mark Ramprakash was often on Sky as a pundit at the same time that he was England batting coach.

Before play begins most days, these former-player commentators are often down on the field, sometimes for broadcast reasons, sometimes catching up with old friends. It's not a new thing, but what has changed is how much players and coaches talk to these former cricketers, and the substance of these conversations.

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"The relationship we have with them works," says Gough, "because they know we still want them to do well. They trust us. They invited us in for drinks. They listen - doesn't mean they'll do it. It's opinion; sometimes you can see more from the commentary box than out on the pitch."

Batty may not be as big as the other names here, but within the spin-bowling and coaching communities, he is a hugely respected figure. He has a player-coaching role at Surrey, and there are very few times he is out on the ground before a match when he isn't chatting to someone from a team. On England's last tour of Sri Lanka, he was in regular contact with Saqlain Mushtaq (then England's spin coach) and Root as the England captain tried to develop his bowling. This tour Gough has talked to England's new spin coach, Jeetan Patel, and Dom Bess. "It's just spinners' union," Batty says. But towards the end of that Sri Lanka tour, SLC offered Batty a coaching role.

In part, broadcasting has changed. Until Simon Hughes started as the Analyst on Channel 4, it was fairly rare for commentators to go into great detail on technical or strategic matters. Now it's more unusual for broadcasters to overlook them.

Team analysts sometimes slip into the Hawk-Eye or TV trucks for intel. Commentators have access to data from CricViz or Opta that allows them to prove a bowler has bowled too short or too straight. Ian Ward gets players to take him through things that have happened in the game, much like a coach would. Star's Select Dugout is a separate service that focuses on in-game analysis and allows for a depth in commentary that isn't usual. (Dean Jones was on recently after he was coaching Islamabad United.) Trent Copeland provides analysis for Channel Seven while still being an active player for New South Wales.

Not everyone is a fan of unsolicited expert opinion; Faf du Plessis would rather players listen to the support staff hired for that purpose Getty Images

As Mark Butcher notes, "Almost all broadcasting is now former players. There was a wall which was journalist v player. That's gone."

Historically there has been a divide between former and current players. Players leave the game and either join the media or, through it, become voices on the game. They often have no real links to the current crop, but they possess strong views that will be reported.

It's why some boards in recent years - among them South Africa and England - have brought together past and present players. The idea is to create some kind of unity between people with the shared experience of having played. In part it is also that if there's a personal link, there won't be as much chirping from former players about the current lot.

Butcher believes Andrew Strauss has played a role in this. "Since Strauss, the players and commentators' relationship is better than before. He encouraged players to chat to Sky and see how things were put together. To learn that it wasn't an 'us and them' thing. We have a job as broadcasters, and they need to understand it a little better."

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Butcher, who stood on the ground at St George's Park that morning, remembers only one occasion in his career when he chatted to a commentator on the field to help his game. "I might have asked [David] Gower once, but it wasn't the done thing." Gough doesn't remember it happening in his time at all.

But modern players are more open to people outside the system giving them help. Players get information from analysts who come from backgrounds of teaching or journalism. They are more open to new ideas and different ways of thinking. Professional athletes want to get better, and they'll use information from anywhere to do that.

When Shan Masood came into Tests, he made 75 on debut and then had a rough patch. He looked like a player who would struggle to hit it off the square and missed out on PSL contracts. Masood went around looking for experts who could help him rebuild his game, among them Gary Palmer (Alastair Cook's batting coach). Since then he has made an impressive return to Test cricket and has upped his scoring rate to be a legitimate option in white-ball cricket.

Those who know van der Dussen refer to him as a sponge. He says, "Obviously not all information is applicable to you, but in general it's better to know more things than you don't. So I listen to as many people as possible to improve myself." van der Dussen likes to look for self-improvement in all facets of his life, so when he heard Hussain had been critical on air, he thought he should go over and take a look. "Maybe he can give me some solutions, if I can call it that, that can apply to me."

With most broadcasters today being former players, the lines between journalist, commentator and coach are blurring Getty Images

van der Dussen thought it was good to watch, even if he didn't agree entirely with Hussain. "I like to hear different opinions. You maybe think you are doing something in a good and correct way, but someone else might see something different. They might see you objectively.

"I am always looking for extra tips and information - try and learn from other people's experience. I try remove myself from the situation. Try to see myself as another player. And if I was another player, how would I try to improve that player? Maybe it is a modern way."

But he understands it isn't for everyone. The day after we spoke, his captain, du Plessis, expressed his reservations at a press conference. "It's dangerous to listen to all the outside influence. As a young player, when great players talk about how you should bat, guys listen because they want to improve. But there is also enough information in our dressing room. Most importantly, it's about trusting what has got you to the level now to be successful and not feel you have to change your game to be successful."

If it wasn't entirely aimed at van der Dussen, it was in part at least.

While some players may not approve, it's clear this by-any-means-necessary self-development is moving into the game. Gough sees it as an advantage for the players. "They're looking for some help with in-game management from someone outside the bubble. In the commentary box we can sometimes see things clearer, without the day-to-day stuff."

South Africa's Rassie van der Dussen watches Nasser Hussain conduct a masterclass

In American sport, teams often have huge backroom support systems. If you're a linebacker, you have a linebacker coach and a large number of support staff who ensure that your performance is the best it can be. Cricket is still a long way off that. Few teams travel with wicketkeeping coaches, and while you may have a spin coach - though that is rare - that person may be a former offspinner and you a wristspinner. The wisdom of crowds allows you to supplement your coaching staff and get a fresh view.

England Cricket recently tweeted a picture of Gough with Mark Wood, asking: "So what's @DGoughie saying to @MAWood33?" Fans reacted with their own jokes - mostly at Gough's expense. But according to Gough, he told Wood: "On this pitch, you know what you are doing, pitch it up, pitch it up." Wood had bowled plenty short or back of a length. When he went full, he got two wickets.

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Around the time van der Dussen was watching Hussain, Broad was expanding in an on-field interview on his chat with Prior, who, he says, knows his bowling better than anyone.

"He said, 'Remember on pitches like that when the teams are too far behind, you don't have to get too funky with legcutters or anything like that. Obviously they have their use. But actually the pressure of the scoreboard, if you bowl your best ball more often than not hitting the top of off stump, batsmen will make mistakes.' So I went in with that mindset yesterday morning."

That ended with Broad taking 3 for 0 in 16 balls. Broad was talking to talkSPORT 2. It was talkSPORT 2 who brought Prior to South Africa as part of their commentary team.