Mercurial is a word that has often been used to describe the enigmatic fly-half play of Gregor Townsend.
Townsend lit up the game of rugby with his maverick talent
The dictionary defines someone of a 'mercurial' bent as "a quicksilver character, cool and wilful at one moment, utterly fragile the next".
Well, if the cap fits - or indeed the 82 caps Townsend won in a long Test career with Scotland.
The 34-year-old, who brought the curtain down on Saturday on an illustrious 17-year career, was blessed with a rare
talent to conjure magic with a rugby ball and was one of the finest playmakers Scotland has produced.
But his willingness to take risks at the very highest level made him prone to the odd fatal gaffe which left him open to, quite often, unfair vilification.
It may be tedious to continually refer to Townsend's gifts as being fragile since he was more often than not a maverick visionary, capable of piercing hitherto unseen holes in an opposition's defence, than gifting interceptions.
John Rutherford, that other legendary Scottish stand-off, says Townsend was a better number 10 than he was.
Townsend shone for club, country and the British Lions.
He made his international debut against England in 1993, coming on as a replacement for Craig Chalmers and saved some of his very best performances for games against the Auld Enemy.
Townsend went on to become Scotland's most capped player in the 2002 Six Nations match with Wales, and racked up 82 caps in total - a record which was only surpassed by Scott Murray earlier this year.
It was just one of those things where you find a hole, get your arm free and someone reads you and runs into that space
Gregor Townsend on the 'Toonie flip'
Among many highlights, one that burns brightly in most people's memory is Townsend's daring reverse-pass, threaded through the eye of a needle, which unlocked the French defence for Gavin Hastings to claim the last-minute winning try for Scotland in Paris in 1995.
Townsend reflected recently on what is also his own personal career highlight.
"It was a tremendous day," he told BBC Scotland.
"There was all the history around the match - I don't think we'd won in Paris for 25 years and to win in the last minute... it was an amazing game.
"It would have been totally different if we'd won 10 points to nil and it was all penalties. For the captain, for such a legend like Gavin to score in the last minute, was fantastic.
"I scored a try early on, it was my first try for Scotland so I don't think anything can top that.
And on what has became known as the "Toonie flip" Townsend said: "It was just one of those things where you find a hole, get your arm free and someone reads you and runs into that space. It's a lovely memory."
Townsend started off as an amateur with home-team Gala
Such supreme improvisation skills often saw him operating on a different wavelength from his team-mates, and he was periodically shunted from his favoured number 10 to centre or full-back, or the bench - or even out of the picture altogether.
Townsend started off in the pre-professional era with his hometown club Gala and set off on an educational rugby tour of the globe beginning with a three-month stint with the Warringah club in Sydney in 1992.
His wanderlust took him to France (with Brive, Castres and Montpellier), to South Africa (with the Natal Sharks and to England (with Ian McGeechan's Northampton).
Townsend soaked up the different rugby cultures like a sponge and attributes his globetrotting as key to his development as a player.
"I really enjoyed my first move to Australia as a 20-year-old when I moved there to play club rugby for three months, that was the fastest improvement in my game," he said.
"It was the catalyst to go and explore and try to get the most out of my game."
In 1997, then-Lions coach McGeechan picked Toonie for the tour of South Africa and he played in the two winning tests, providing the perfect foil in between Matt Dawson and Scott Gibbs.
The longer I go on, the Lions experience was so special and to win with the Lions was probably the pinnacle of my career
"The longer I go on, the Lions experience was so special," Townsend said.
"And to win with the Lions was probably the pinnacle of my career."
He was at his best feeding off the lavishly talented John Leslie in Scotland's exciting last-ever-Five Nations-winning side of 1999, with Townsend scoring in every game.
The unfortunate demise of the Border Reivers cast a slight shadow over Townsend's farewell appearance at Netherdale, the home-turf on which he took his first hesitant steps in the game as a five-year-old with Gala's mini-rugby team.
But true to form, he delivered a parting shot to the head honchos of Scottish rugby on the state of the game north of the border.
"The whole of Scottish rugby has failed to get pro rugby going the way it has in other countries," Townsend said.
"Since 2003 the northern hemisphere has really grown - in France it's huge and in Wales it's really finding its feet and growing after a few teething problems.
"In Ireland it's always been strong and it's the same in England, so we're the odd ones out.
"Everyone who's been involved in the last 10 years, players, coaches, administrators have to take the blame for that."
Townsend saved many of his best performances for Scotland
And on the controversial disbandment of the Reivers, Townsend again pulls no punches.
"The decisions have to be made by those at the top of the SRU," he said.
"But I think everyone in rugby knows that three teams is the minimum for any serious rugby nation to compete at the highest level."
"Wales have showed that with four teams and Ireland have four teams and it would be great to aim for four teams.
"So, in terms of your finances, I'd say make saving the three teams a priority because the consequences in a few years time will be poor for Scottish rugby."
Townsend is somehow a fitting Scottish sporting hero, cut from the same cloth as those other so-called 'mercurial' talents; like his Jinky footballing equivalent, Jimmy Johnstone, the elusive Jim Baxter, Formula One's Jackie Stewart and cycling's forgotten man Robert Millar.
Like Townsend, we forgave them their occasional clanger given that they sprinkled such memorable stardust over their respective sports.
Hey, even Gavin Hastings made mistakes!