His first contribution was at the crisis meeting that followed the thrashing in Penrith, when the team sat equal last on the NRL ladder.
"We spoke in front of each other - we talked about what we thought our best attributes were and what we needed to get better at," says Nielsen.
"I told them I had been in a worse situation than this, in a season where we played 90 per cent of the games for no points at all [at the Storm in 2010 following the salary cap scandal].
"I said, 'Don't get your heads down, we have a chance to turn this round; keep your heads up, believe in yourselves'."
Nielsen returned to the field for the win over the Knights in round 11 and he has been ever-present since.
The former State of Origin centre is not the type of player that grabs the headlines and the 28-year-old tends to polarise fans. He's solid rather than spectacular, efficient instead of eye-catching. Along with Thomas Leuluai, he is the defensive rock in the Warriors' backline, a man who holds it all together with the plethora of attack-minded players around him.
He's the kind of player that every club needs, the type that coaches tend to love.
"His influence on our defence has been quite profound," says coach Matt Elliott. "His individual defensive game was probably best emphasised when we played the Broncos and he shut down Justin Hodges. For me, he has been in our best two or three defensive players, week-in, week-out."
Attack remains the work-on. He tended to grab a few poacher's tries (he averaged seven tries a season over the last three years) while at the Storm but has yet to threaten much offensively for the Warriors.
Nielsen, who carries the nickname 'Danger', is conscious of that but says he is still learning to read what is happening inside him, especially with the unpredictable Feleti Mateo and Shaun Johnson working their magic.
"Dane has underestimated his attacking qualities," says Elliott.
"He's heard from a lot of people across the years that he is a good defensive centre; he is, but he has a lot more to offer than that.
"We've had a chat about that and he has that expectation on him now. I've already noticed the difference."
The last time Nielsen came up against his former club was a painful experience, as he aggravated a rib injury picked up the round before and spent another three weeks on the sidelines.
The Warriors competed well in that Anzac Day clash, leading until the 70th minute before the Storm scored two late tries.
Melbourne have lost three of their past four games and look vulnerable, but that was without the 'Big Three' of Cameron Smith, Cooper Cronk and Billy Slater, who all return today.
This match may be season-defining for the Warriors.
A victory would be a massive step towards the finals, not just in terms of competition points but also the intangible boost to confidence and momentum from beating the NRL's benchmark side.
A loss would not be the end of the road. The Warriors still have three more home games before the end of the season - Sharks, Panthers and Raiders - but a good performance against the defending premiers is vital.
"We need to be strong [today] and solid," says Nielsen. "When we go away from our gameplan it usually takes its toll.
"When we try to push something that isn't on or don't get to our kick on the fifth tackle it really hurts and puts pressure on us. In this game, especially against a team like the Storm, you have to be consistent and build pressure, otherwise they are building pressure on you. Obviously we have improved a lot but if we want to be there come semifinal time we have to keep doing that."
