Van Rooyen kicked one goal, assisted another and provided a focal point in attack after Harry Petty was substituted out with a foot injury in Saturday's 15.13 (103) to 7.7 (49) win at the MCG.
The performance brought an end to a trying week, during which the 20-year-old's controversial two-match suspension was upheld by the tribunal before Melbourne had it overturned on appeal.
The saga played out amid fierce debate around van Rooyen's mistimed spoiling attempt on Gold Coast's Charlie Ballard and the subsequent 'striking' charge, which Goodwin feared could have changed the fabric of the sport.
"It was a brilliant opportunity for him. He's a 20-year-old lad that went through an enormous week," Goodwin said.
"Whether he was going to play or not, we spoke to him about his ability to be able to deal with that, and also if he got through that his ability to be able to come out and perform.
"He only kicked one (goal) on the scoreboard but he had five or six marks, 14 touches and competed really strongly all day.
"With Petty going off the ground, he gave us a really great aerial contest ahead of the ball."
Midfield stars Clayton Oliver (34 disposals), Christian Petracca (30) and Jack Viney (31) were also important in delivering a result that could leave Melbourne (7-2) sitting on top of the ladder at the end of round nine.
Petty kicked two majors, as did Charlie Spargo and Bayley Fritsch, while All-Australian defender Steven May marshalled the back-line in his 200th game.
A sixth-straight defeat was another tough pill for Hawthorn to swallow in a difficult season.
The Hawks were well off the pace in the first half, with their woes compounded by injury issues for James Blanck (corked quad) and late withdrawal Ned Reeves (ankle).
Melbourne's control was established early as their dominance around the contest led to a 23-0 head-start and a 34-point advantage at quarter-time.
The Hawks' only goal of the first half was fortuitous, coming through Mitch Lewis when the key forward was not penalised for a push in May's back.
Jai Newcombe (26 disposals), Will Day (29) and James Worpel (26) breathed life into the contest as Hawthorn showed fight, outscoring their opponents in the third term and trimming the margin to 27 points.
But the Demons had too much polish and a greater spread of contributors, and were never seriously threatened before kicking clear again in the final term.
"Melbourne are a good side and we had no answers for them early in the game," Hawks coach Sam Mitchell said.
"I was pleased with the resilience of our group and the fact that we found a couple of things in the game.
"But really I looked at Melbourne and they're a pretty impressive unit."
