Florida Panthers coach Gerard Gallant didn’t realize how valuable Reilly Smith would be to the team after arriving via trade from Boston last summer, but it wouldn’t take long to learn.

“I didn’t know much about the kid until we got him, but he’s been steady all year,” Gallant said on a conference call Monday. “He kills penalties and plays power plays. … He shoots the puck real well and he makes plays real well and he’s consistent every night. He comes ready to play and he’s a guy that doesn’t pass up shots, and that’s why he’s scoring goals.”

Though the Panthers trail the Islanders, 2-1, in their opening playoff series, Smith, 25, has been the most dominant player in the first round, leading all players in the postseason with eight points (four goals, four assists).

He now has three straight multi-point games and a plus-seven rating.

“I think we’re playing well, we’re doing a lot of little things well,” Smith said of his line’s play. “We’re recycling pucks really well and we’re making their defense work. Seems like we’re doing that or finding each other or finding an open spot. We’re gonna keep doing that and hopefully we can still get a couple more bounces.”

In Game 3, Smith scored in the opening minutes for the second straight contest – he hit the crossbar later in the period – and then added two assists to give the Panthers a 3-1 lead, though Florida fell 4-3 in overtime Sunday night at Barclays Center.

“It’s a little frustrating that we’ve done such a good job closing teams out all season and then in playoffs it’s been the opposite way,” said Smith, who scored a career-high 25 goals this season. “We’re just gonna have to work on that.”

Center Vincent Trocheck (ankle) has yet to appear in the series, but the Panthers’ third-leading goal scorer skated Monday and may practice with the team on Tuesday.

Florida goaltender Roberto Luongo said he was “pretty exhausted” after playing three games in four days, but Gallant said the 37-year-old will be back in net for Game 4 on Wednesday.