The second rows have been locking horns since they were Under-20s and this Saturday afternoon at the Aviva Stadium will see them reunited once more when Ireland host a South African side captained by Etzebeth in the home side’s Guinness Series opener.
Etzebeth, who turned 26 a fortnight ago, is four months Henderson’s senior and was a fledgling Test player with a burgeoning reputation when the Ulsterman came off the bench in Dublin for his Ireland debut in 2012.
Declan Kidney’s side lost 16-12 to the Springboks that evening, and after three Tests on tour in South Africa in 2016, Henderson has just one victory against his abrasive rival, not including the 2011 Junior World Championships in Italy.
“In Italy, yeah,” Henderson recalled. “He was a year above me. Unfortunately, both of the games didn’t go our way.
“You could tell when he was younger that he was a natural leader and a leader who captains through what he does rather than speeches or trying to emotionally rile guys up. That’s from an outsiders’ point of view, I’m not sure what he’s like to play (with) but you can tell he’s a massive presence to play alongside.
“I played against him a good few times before, he’s a massive presence on the pitch and a huge leader in their team, captaining them now. He’s been very good for them, not only in the tournament just passed, but in the last number of years.”
Such is Etzebeth’s ability to impose himself through his physicality, 6ft 8in frame, and confrontational approach that control of a game can quickly slip from an opposition’s grasp if he is given the freedom to do so.
“His performances add to his presence and size and the way he carries himself and I’d say the work he does off the pitch would probably match that to make him the player that he is.
“He’s alongside a few other boys, Lood de Jager and (Franco) Mostert, they’re all enormous presences, Pieter Steph du Toit as well. They’re all probably what you’d describe as your traditional South African rugby players.
“Having played against him three times last summer, we know that’s something we’ve learned lessons from. Probably good lessons and bad lessons. Lessons in how to shut them down and lessons on how maybe, if you don’t shut them down they can definitely take hold of the game pretty easily.
“We have to look back to other games we played where we’ve had to shut down big threats, be it in the Six Nations or previous tours, we’ve had to make sure boys aren’t taking hold of the game and leading the opposition as well as they should be.”
The 2016 summer tour was bittersweet given the heroic victory in the series opener at Newlands, when Ireland won on South African soil for the first time, despite CJ Stander’s first-half sending off followed by a Robbie Henshaw yellow card.
When the Irish took a 19-3 half-time lead at altitude at Ellis Park, Johannesburg in the second Test a week later, further history was in the offing with a series win within reach but those hopes were short-lived as the under-pressure Boks rallied to power to a 32-26 victory. The decider in Port Elizabeth also slipped from Ireland’s grasp and Henderson agreed it was an outcome that still rankles.
“The first game was fantastic — 14 men for a lot of the game, 13 for some of it and still to come out with a win. Then, being so far ahead in another Test and slipping off it was something that was massively frustrating.
“We could have made history going down there to be the first team to turn over South Africa on an incoming series. But that’s something a wee bit annoying for us and something we realise, it was in our hands to take it. It slipped off the ball in the second half.”
While his debut against the Boks also ended in defeat, there are much happier memories for Henderson from that 2012 evening, up against Etzebeth and future Ulster back-row team-mate Marcell Coetzee, particularly as he was somewhat mystified by his elevation to Test rugby.
“I just remember that I had only really started playing for Ulster at the time and I thought it was very bizarre,” he said.
“Looking back now I understand why no-one ever selected me until I made my international debut. I was young and raw and inexperienced and probably didn’t have a bit of a clue what I was doing. That’s what I think now, looking back.
“But it was obviously a coach had faith in me and sort of saw what they could potentially mould out of this 20-year-old kid who didn’t really know what he was doing. Looking back I loved it at the time, it was fantastic.”