Following a 4-1 loss to the Tampa Bay Lightning, Roy didn't sugarcoat his thoughts on Duclair's play in which he posted a -1 +/- in 12:15 ice time.
"He was god awful," said Roy. "He had a bad game. That's why I didn't play him a lot. He is lucky to be in the lineup. Sorry if I lose it on him right now, but that's just how I feel. He's not skating, he's not competing, he's not moving his feet. He's not playing up to what we expect from him. I think it's an effort thing."
Roy told reporters on Thursday that Duclair was not on the ice for practice despite the two having a private conversation prior in order to address the situation.
The Isles coach said went on to say he gave Duclair the time he needed to reflect on the incident.
"We'll give him all the time he needs," said Roy.
Duclar is currently under a four-year contract worth $14 million and has posted a career-worst -15 +/- this season.
The Islanders' woes continue as the team, which was once at the bottom of the Metropolitan Division and then skyrocketed to a possible Wild Card spot, have now lost six straight games - falling further out of the playoff race.
Earlier in the season, star player Mat Barzal made a brutal comment about the embarrassing fans' attendance in the middle of the game.
The Islanders are currently 32-32-10 and are six points out of a wild card spot with just a handful of games to go.