Andrea Pirlo was untouchable at the height of his playing career, a footballer whose grace and prowling presence drew widespread admiration and struck fear into rival teams.
As a coach, we can surmise but really it is a guessing game as to what we will be getting from Pirlo as the dugout rookie leads Juventus into the 2020-21 season.
On Sunday evening in Italy, the man who was a World Cup winner in 2006 takes charge of his first Serie A game with Juve, who play Sampdoria in Turin.
Maurizio Sarri's Juve reign lasted just one season, albeit another Scudetto-yielding campaign for the most successful club in the league's history. Pirlo will be expected to deliver at least that level of success, and encourage a swagger too.
He joins a host of significant former players plucked for leadership roles at an elite level, typically on a hunch rooted in familiarity, the chosen ones often still fresh from their playing days and with scant experience to call on. Top marks in coaching exams provide no guarantee that success will follow.
Many times, the gamble on a colt coach has paid off, with presidents and owners rightly sensing the novice harbours the innate expertise to lead and to inspire, and crucially to bring results. On other occasions, it has ended in frustration and tears, and in some instances the jury remains out.
Here is a look at just some of those cases, illustrating how there are no guarantees attached to such appointments.
The go-to example for any club that wishes to justify appointing a club legend to sudden seniority on the coaching side, former midfield general Guardiola was just 37 when he took charge at Barcelona in 2008, after a year coaching the B team. He departed four years and 14 trophies later, including three LaLiga titles and two Champions League triumphs, and was vaunted as the world's best coach.
Further successes have come with Bayern Munich and Manchester City. Plainly, Pep was born to lead and Barcelona were wise to the fact.
How would Zidane, the mercurial playmaker – the only rival to Brazil striker Ronaldo when assessing the greatest player of their generation – take to coaching? Could the erstwhile Galactico tease out the best from those who can but dream of matching the twinkling feet and god-gifted balance with which he was blessed? Could the former Real Madrid maestro really be a suitable fit for the Bernabeu job that has swallowed up many an experienced coach?
Three Champions Leagues and two LaLiga titles later, we probably have a decent idea of the answer to those questions. There have still been ups and downs, and a brief split along the way, but 18 months in charge of Madrid's B team – Castilla – hardened Zidane for the obstacles he would face in the top job. His Madrid sides have at times lacked the verve that was his signature as a player, but they have delivered results and abundant trophies, and ultimately that is what counts.
Before there was Zidane, France had Platini. A wonder of an attacking midfielder with Nancy, Saint-Etienne and Juventus, Platini was also a goalscoring titan of the France team that won Euro 84 and reached semi-finals at the 1982 and 1986 World Cups. It followed, to those that knew him, that Platini would go on to become a great national-team coach too, and at the age of 33 he was appointed to lead France, having retired as a player a year earlier. Platini took over with France already at a low ebb and defeats under his charge against Yugoslavia and Scotland meant they missed out on reaching the 1990 World Cup.
Could Platini bounce back? It seemed he might when France reached Euro 92 in style, with eight wins from eight qualifiers, Platini nurturing the likes of Didier Deschamps and Laurent Blanc, but Les Bleus flopped at the tournament itself as they and England bowed out of a group from which Sweden and Denmark advanced. Platini resigned not long afterwards, began to forge a solid reputation in football administration, and by the late 1990s had built a strong, ultimately fateful, alliance with the then FIFA secretary general Sepp Blatter. He would never coach again.
If there were ever a case of being blinded by celebrity, then some of the presidents who have given Diego Armando Maradona coaching work surely have fallen victim. The biggest star of his generation, Maradona retired from playing in 1997 and, with barely a sniff of coaching experience and just about as much baggage as an airport carousel, was named boss of his native Argentina in 2008, tasked with taking the Albicelestes to the World Cup two years later. Argentina scraped their way into the finals and were thumped 4-0 by Germany in the quarter-finals. Maradona's contract was not renewed.
He has continued to pick up coaching work, one curious-looking appointment after another, most recently with Gimnasia in the Argentinian top flight. Maradona the coach has been no match for Maradona the player, and it was naive surely for anyone to think that was ever remotely possible.
Pirlo was an artist of the 21st century game, and he is considered a deep thinker, while the common theory is that English midfield counterpart Lampard achieved much of his success through hard graft and maximising his rather more rudimentary talent. Whether either categorisation fits the bill is a moot point, but Lampard has a wiser head on his shoulders than many footballers, was top of the class in his school days, and his IQ is reputed to be through the roof.
Derby County gave him a first break in coaching but it took Chelsea just a year to pounce and parachute Lampard into his first Premier League manager's job. A Stamford Bridge great as a player, Lampard had an acceptable first season as Blues boss but the acid test comes in this new term after a spree of big-money signings. A high-stakes London gamble will play out in the coming months.
As Pirlo takes charge of those in the Bianconeri stripes he once wore – Cristiano Ronaldo and all – it bears remembering that returning black and white messiahs can fail. Former Newcastle United striker Shearer returned to St James' Park in April 2009, the club's record goalscorer aiming to rescue the team from the threat of relegation, but a dismal return of five points from eight games saw them sink out of the Premier League.
Shearer left and has not coached since, happily staying in his niche as a television pundit. There are pressures but also a certain comfort to that studio role. Two months at Newcastle was the sum of Shearer's coaching career: as Pirlo may yet find out, that can be all it takes to destroy the notion of it being a natural next step.