aside from the goal how did he play
If you're Canadian and you are subscibed to Bell you can see it on "on demand". As for Lafreniere he had a quiet 1st period but a very strong 2nd and 3rd. Thomas got hurt in the 1st and they put Lavoie with Alexis and Dellandrea. They have been flat out dominant. Lafreniere showed great combativity, skills and IQ again. Winning battles against the board, controlling puck down low, making nice pass to his teammates and helping defensively.
In the first period he was trying to catch Boqvist who was able to generate a quick wrister to score a goal. He was a little late on the play but he was still the 3rd man back of all the forward. Even though his coverage wasn't adequate, it shows that he has some defensive IQ as he took the center's position (Thomas at the time).
Worth mentionning that in a pre game interview he said he'd like to improve his defensive game because he wants to become a complete player. He consider himself as a playmaker who can score.