They have known each other a long time, and each knows what the other has to offer.
At the stage of the campaign where faith and reliability are vital ingredients, Ulster's hope is that the history and chemistry between the pair bears fruit.
"He knows me," Nick Williams says of Mark Anscombe.
"He knows me better than anyone else in this squad knows me – better than anybody anywhere else in Northern Ireland.
"We have a lot of history, we go back a long way and I'll be honest with you – he brings out the best in me.
"I don't know what it is about Cowboy, if it's the game-plan he tries to put forward to us or whatever.
"But the little chats he has with me always hit home and that's what I love about working with him.
"There's mutual respect. We can always have a bit of craic, a bit of banter, but when it comes down to it he always seems to bring the best out of me," explained Williams.
And with tonight's match against fourth-placed Glasgow Warriors at Scotstoun being followed by a home date with Leinster and a trip to Munster, the 30-year-old, 6ft 3ins (1.91m), 19st 5lbs (123kg) Aucklander knows Ulster need him to be at his best right now.
It's a daunting run-in as Anscombe's men attempt to nail down a play-off place and, best case scenario, a home semi-final.
To get that, they must be first or second at the end of 22 rounds of PRO12 fixtures.
"You'd probably want to have these three games before you go into a semi and a final," said Williams, seemingly unfazed by the magnitude of the challenge.
"You don't want to go in under-cooked so I see it as a good thing.
"You always want a few hard tests before you go into the real big boys' games," he added.
Asked if he believes Ulster will be hosting a Ravenhill semi-final four weeks hence, his reply is instant.
"Yes – without a long pause!" he hits back.
"This is why you play rugby; you want to play against the best teams, but at home if you can. There's always been that goal for us from the beginning of the season – we wanted to play as many big games as possible here at Ravenhill," he said.
"That's the reason why they've done it up – to host big games.
"If you ask any of the guys on our team if a home semi-final is a realistic goal, they'll say yes."
Williams insists that the disappointment of Ulster's Heineken Cup quarter-final exit at the hands of Saracens has served only to sharpen the players' appetites for the fray and a trophy.
The fact that they do not have much time left together as a group is a huge motivating factor.
A few weeks from now, Johann Muller, John Afoa and Tom Court will have moved on.
As a squad, Ulster's players are determined to land silverware before those three big forwards head off.
"We know what we're playing for," said Williams.
"We know we're not just playing for the people who come out here and support us week in, week out – we're also playing for our pride and for the brotherhood that we've been able to create here," he stated.
"There's a bond that I don't think I've experienced anywhere else and it's not just among the homegrown players – a lot of us foreign boys have come in and have bought into that Red Hand on the jersey.
"We want to give something back, not just to the fans but to the likes of Muller and Afoa and Court – the boys who are going to be leaving – so I think that's creating an extra 10-15 per cent in us."
Following last season's heroics which saw him win the Irish Rugby Union Players Association's Player of the Year and RaboDirect PRO12 Player of the Year awards, Williams admits 2013-14 has been a difficult campaign.
But he feels he has come back to form at just the right moment.
"You like to be playing at your best during the big games and I'm happy to have hit a bit of form, possibly at the best time of the season when we're coming up against the three best teams we face in the competition," he commented.
Asked about tonight's opponents Glasgow, he replied: "Tough. No superstars, just real grinders who love the physicality.
"They're typical Scottish guys – I can just see them running around in kilts...
"I watched their game against Munster at the weekend and they were unbelievable.
"Munster maybe had a bit of a (European) hangover after their Heineken Cup win, but Glasgow beat them at their own game so fair play to them.
"And we know that's where they're going to come at us, too.
"They're going to try and beat us up physically.
"But, like I said, these are the games you want to play."
Meanwhile, Warriors coach Gregor Townsend said his side would put the win over Munster out of their heads.
"Last week was a precious win for the club but we have another huge game in prospect at Scotstoun," said Townsend.
"Ulster are coming to Glasgow high on confidence and ahead of us in the league – so it's a very important game for both clubs.
"What impressed me most was our players workrate and how we kept taking the game to Munster. We'll need to repeat that effort again."
Even with full-back Jared Payne sitting out the second match of two-games ban and Stephen Ferris re-joining Ulster's lengthy injury list, coach Mark Anscombe has been able to name a strong 23-man group for tonight's crucial game against Glasgow Warriors at Scotstoun (7.35pm).