Ulsterman Armstrong is on firm ground as he helps put sting back into Wasps
There will definitely be one very tense Ulsterman at the Aviva Stadium today as Leinster and Wasps battle it out for a place in the European Champions Cup semi-finals.
Up in the stands, David Armstrong will be doing his usual on match day; intently following the action and living every moment while Wasps go about their business in their still achievable bid to secure a European and domestic double.
And for him, the now Coventry-based side is very much his business as the 52-year-old from Belfast is Group Chief Executive Officer at the hugely ambitious club and the man responsible for overseeing the successful acquisition of the 32,600-seater Ricoh Arena which saw Wasps relocate to the West Midlands from their traditional London base in 2014.
And even though the move from the capital was both risky and controversial - Wasps were ground-sharing with Wycombe Wanderers prior to the move - it has paid off handsomely and, under Armstrong's watch, the club are now going from strength to strength both on and off the park.
But it's not just the club which has made a journey to reach this point, the Ulsterman has too - though there is no doubting his impact since coming on board in 2014.
The revenue streams which are now part of the group operation in Coventry - the Ricoh contains a casino and hotel, as well as hosting exhibitions, high-profile concerts and having a professional netball team, while Coventry City FC also use the facility - have all contributed to the club now boasting the largest turnover in world rugby and after posting £30.9m last year they are closing in on hitting £40m this year.
Armstrong's considerable business acumen and commercial experience have all fed into where Wasps - currently Aviva Premiership leaders with their play-off place secured - now find themselves with a powerful squad and strong crowds to match.
"Wasps needed to move and we needed to own our own stadium so the opportunity to buy the Ricoh Arena was just too good to turn down," Armstrong explained.
"It needed us to be brave to move the club 150km, but it was the best way to sustain its future financially and to open a new era.
"It was a risk, but the great thing about our business model is that it's only one third rugby and two thirds everything else.
"But we're a rugby club and we'll always be a rugby club and the fact that we do other things is only about furthering our ambitions in rugby."
And what of his own journey?
After leaving Northern Ireland at 18, where he was educated at Campbell College, Armstrong studied Accounting and Computer Science at the University of Kent.
He then worked in the City and put down roots in Surrey with wife Sinead and children Sara-Jane (now 21) and Jamie (19).
A chartered accountant, he worked for Diageo, PepsiCo, Compass and McArthurGlen and was Group Financial Director of Lonrho.
As he puts it, he came to Wasps "through quite a convoluted route" though his interest in sport, and in particular rugby, meant that he already had some involvement in the game.
Armstrong's son Jamie played at the Effingham and Leatherhead club in Surrey, and Armstrong ended up coaching and helping out before becoming chairman, a position he still holds.
And then, through his work for the Compass Group, he founded the RFU's successful hospitality business known as the Twickenham Experience.
And Wasps? The club's then CEO Nick Eastwood - now deputy chairman - was already aware of Armstrong's abilities and approached him over the planned purchase of the Ricoh Arena.
"I led that process," said Armstrong. "And then Derek Richardson, our owner, said 'why don't you just stay on as CEO and run the whole thing?'
"So I thought, 'that's a good idea' (he was appointed in March 2015) and I've now been involved with Wasps for three years in June."
Highly knowledgeable about the game, Armstrong is also hands-on when it comes to the transfer strategy and building the star-studded squad, which last season included current Ulster ace Charles Piutau who was a huge success there.
He is also one of several exiled Ulstermen at the heart of English rugby with fellow Belfast man Jim O'Toole the Chief Executive at Worcester Warriors while Mark McCall is Director of Rugby at Wasps' arch rivals Saracens and David Humphreys is in the same role at Gloucester.
As Armstrong pointed out: "When we get together we chuckle amongst ourselves that there are so many Ulstermen involved in Premiership rugby."
Away from the game, he plays tennis and golf while motorsport is also a passion and he takes part in European road rallies, such as the Mille Miglia in Italy, while he is also on the board overseeing the World Athletics Championships in London this summer.
He spreads his time between home in Leamington, outside Coventry, and the family base in Surrey and still returns to the province on visits to his father while he also has cousins here.
The Ulsterman has certainly ushered in a new era for Wasps but, as he points out, on-pitch success is what really counts and the club need that having last won a Premiership title nine years ago, while a decade has passed since they were European champions.
"Rugby clubs aren't measured by wealth, they're measured by trophies," he pointed out.
"We've achieved a lot, but there's an awful lot more we want to do."
Beating Leinster will do very nicely as part of that process.