“I’ve loved the last three or four years but it’s been tough. There’s still more to be achieved. I appreciate everything he has done for me personally but as a team he’s done loads for us and will be missed.
“Willie is really big on world-class effort, which is not always outcome-based but effort-based, and that comes from training and your pre-season.
“You saw on Friday night that we scored a lot of points, and some nice tries, but it came from our defence and that’s always been the focus, and where our success has come from.
“From day one he set his tone, and told us how he wants his team to look. That comes from training. The training is pretty tough and intense, especially pre-season, but you get the rewards off the back of that so it’s been a good three or four years.”
Hadley said nothing has changed in the wake of the news, and that Peters and his players are intent to build on their unprecedented trophy clean sweep.
Hull KR are ninth in Super League with two wins and three defeats from their first five matches and play Hull FC in the 250th Hull derby on Friday (12:30 BST).
Hadley said: “He’s as keen as ever, he’s intense, he’s detailed to everything, game day and training. He’s always on it. The hunger and drive to be successful is still there, if not more.
“We’ve created some good memories and there’s more to come. We’re hungry for more trophies and that’s the message.”