Drafted third overall by the Tampa Bay Lightning in 2013 and cut from his first training camp, Drouin played most of this season but just three games in the playoffs. He made his Cup final debut in Game 2 against Chicago Blackhawks on Saturday night.
Along the way, Drouin has learned from his experience on the ice and watching from above.
"I didn't come in thinking it was going to be easy," Drouin said Saturday morning. "You want to be in every night, but it's definitely a harder league to just come in and start playing. There's stuff you've got to learn before you come in and make an impact right away."
If it was Drouin's choice, he would have been in the lineup for the Lightning's first 21 playoff games. He had four goals and 28 assists in 70 regular-season games played mostly as a 19-year-old.
But coach Jon Cooper instead opted to keep 36-year-old veteran Brenden Morrow in the lineup, at times going with 11 forwards and seven defencemen or play Jonathan Marchessault instead. Drouin has been frustrated but said he understood the situation.
"Look at our team, our depth," the Huberdeau, Que., native said. "They're the reason we're in the Stanley Cup. We have a lot of good forwards and a lot of good D. It's a hard lineup to crack."
Drouin's superb offensive potential could one day make him an NHL superstar. But at 20 his 200-foot game needs work.
"Offensive skills, there is no question he's fun to watch," Cooper said in New York during the Eastern Conference final. "There is more than one net in a rink. There's two. So you have to be able to play in front of both of them."
Drouin's only previous playoff action came in Game 4 against the Detroit Red Wings, then Games 3 and 4 against the Montreal Canadiens. He didn't register a point and didn't see the ice in the conference final.
His work has come after practices and in the gym, and Drouin said he feels a little stronger.
"Our trainers have been great," Drouin said. "We do workouts, we skate after when we don't play. And I think they try to keep us as close to game shape as possible."
Cooper expects Drouin, Marchessault, forward Vladislav Namestnikov and defenceman Mark Barberio to be ready at all times. They've all appeared in these playoffs.
"Your job as a player, you have to be a pro," Cooper said Saturday. "You have to make yourself ready."
The past two years have made Drouin ready, mostly since he made his NHL debut in October. He figured out the speed and size of the NHL and found a comfort level.
"It's not really something you can explain. You just learn," Drouin said. "From our team, I think the veterans have been great with me throughout the year and still are."
Drouin pointed to Morrow as a specific veteran who helped him "gain as a person" through habits more than advice.
"You look at those guys, they're so professional," he said. "They show up every day, they do the same routine and nothing really changes. You look at Morrow, you know where he is 10:30 every morning."
Drouin's path has been a bit different from Blackhawks phenom Teuvo Teravainen, a 2012 pick who was able to spend time in the American Hockey League this season because he's 20. Teravainen was scratched five times in these playoffs but had two points in Game 1 and isn't going anywhere.
Cooper said "it's easy to put similarities to the two because of the elite skill level," but added that they're different players. All along, Tampa Bay's coach has said Drouin could get in to the Cup final at some point.
"Jo, he's a talented player," Cooper said Saturday. "We've watched him grow this season. He gives us a different look when he's in the lineup."
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