One of the most intriguing factors of international cricket and indeed all team sport is the throwing into direct opposition players or coaches who have been the firmest of allies. From fighting a common cause to head-to-head rivalry always adds spicy anticipation to proceedings.
Jack Charlton was a defensive rock for England when they won their only football World Cup in 1966, but managed the Republic of Ireland in Italia 90 with the direct intent of stopping them winning another.
Cricket history is littered with poignant cases. Ian Botham, so tight an ally with Viv Richards and Joel Garner at Somerset that he resigned in protest at their sacking, would be under relentless attack from the West Indian pace barrage in the international arena.
The great Iftikhar Ali Khan, the Nawab of Pataudi, played for England in the infamous Bodyline tour of Australia under Douglas Jardine and indeed scored a century on his Sydney debut. Jardine's tactics, however, did not sit well with the Nawab. Pataudi famously expressed his unwillingness to field in the "leg-trap" with Jardine retorting: "I see his Highness is a conscientious objector" and further adding "you will never play Test cricket again".
Pataudi was to play Test cricket again 12 years later though, when he captained the Indian team on their tour to England in 1946. On this occasion though, his former country carried the honours, despite his personal healthy 46 average.
Global franchise cricket makes these rivalries commonplace of course, with players both aligned and in opposition on a regular basis. The friendly nature of post-match interactions emphasises the bonds they have built when on the same side elsewhere.
Tomorrow's IPL encounter between KKR and the Sunrisers throws up just such an encounter when KKR captain Eoin Morgan saddles up his Knight Riders against the Sunrisers, coached by Trevor Bayliss, the man with whom he reshaped England's white-ball cricket, culminating in that pulsating World Cup triumph at Lord's in 2019. Throw in for good measure that Bayliss was also once coach of KKR, leading them to the 2012 IPL title and Champions League qualification.
The Australian was appointed by Andrew Strauss in 2015, to turn around England's fortunes following their dismal showing in that year's World Cup in Australia and New Zealand, with the express remit of delivering a side that could win the next tournament, in four years' time, on home soil.
That goal was achieved in spectacular fashion in a final for the ages against New Zealand at Lord's in July, a result that Bayliss described as the "cherry on the top" of his time in charge of England's various squads.
Whilst it was, undoubtedly, very much the cherry, Bayliss was keen to highlight that perhaps the real achievement was the change in attitude from top to bottom in England cricket. "A change of attitude [was required]," he told Sky Sports. "A change of the way we played the game. Looking back to the 2015 World Cup, England probably played the game in a little bit of an old-fashioned way, and my role was about bringing in players that were more attuned to playing the more modern style of game.
"But it was about attitude as well, about the knowledge that whoever won that World Cup was going to have to play some bold cricket, and we stuck to our guns through those four years, and through some tough periods as well."
Alongside him all the way was Morgan, the man from Dublin, and KKR captain, who shifted his allegiance from his native Ireland to lead England to their current status as white-ball kings and World Cup holders. Indeed, it was Morgan who endorsed Bayliss's England appointment, saying: "I'd played two seasons under him for KKR in the IPL and I was a big admirer.
"One of Trev's biggest attributes is that he takes pressure away from players. There's always so much pressure, anyway: from your own internal hopes, from your friends, your family, and from the media. You don't need more. He is a very calm, very personable man. He asks good, relevant questions, and that sparks great conversations. That creates a really good learning environment."
With his ever-present floppy hat and laid-back demeanour, Bayliss can be all too easy to underestimate. His dress sense tends to make Worzel Gummidge look like a fashion mannequin. Indeed, when his car was broken into in Manchester in 2019, his clothes were the only things stolen.
"Apparently police are looking for the worst dressed thieves in the city," he said with a smile.
However, just consider his record. As well as a World Cup victory, he has won the IPL twice. The Sheffield Shield twice. He has won the Big Bash, the Champions League, and as England's Test coach, has beaten South Africa home and away, defeated Sri Lanka away, won an Ashes series in England, and never lost a home series. He has coached teams – Sri Lanka and England – to three other global tournament finals.
When it became clear he was in the market for another job, it seems he had a choice of three IPL teams, but perhaps appropriately given the floppy hat, it was the Sunrisers he chose.
In this IPL, Bayliss has in his charge with the Sunrisers two aggressive batsmen whose careers he has impacted in Jonny Bairstow and Jason Roy. He'll face others with the likes of the Rajasthan Royals trio of Ben Stokes, Jos Buttler and Jofra Archer if he is fit enough to play at some point, Sam Curran and Moeen Ali at Chennai, and Chris Woakes and Tom Curran with Delhi Capitals.
However, like Sir Alf Ramsey and Bobby Moore or Sir Clive Woodward and Martin Johnson, the Bayliss and Morgan partnership is deeply etched into English sporting history. No franchise rivalry will diminish that, but the two know each other's games and approaches well, so expect no quarter given when the two proven winners come head-to-head in Chennai.