Andrei Vasilevskiy led the Lightning out for warmups and was scheduled to start but was a late scratch. Johanson, who last played against the Philadelphia Flyers on March 13, made 27 saves in the first two periods.
"I don't know if he was the player of the game for us or not, but he should have been," Lightning coach Jon Cooper said of Johansson. "It's a tough spot to be in when you're not the goalie that's playing every second night and being in a rhythm. And for him to come in and keep doing the job he's doing, it's a tribute to him."
Point's second goal made it 4-0 at 19:43 of the second period, a one-timer from the left circle off a cross-ice pass from Kucherov.
"We've had a lot of things go our way on this homestand, but we earned them," Cooper said. "The only difference tonight was that we had a 4-0 lead, but if I've got to be honest, we didn't deserve that 4-0 lead. Learning experiences come in so many different ways, shapes, forms … maybe the best ones come when you can sneak away with a win and you get to learn from that as well."
The Islanders then scored three goals in 2:49 in the third period.
Pulock cut the lead to 4-1 with a power-play goal at 5:58 of the third period with a slap shot from the point before Gatcomb made it 4-2 at 7:47 with a wrist shot from the right circle.
"We have to come out with that same intensity that we had in the third," Pulock said. "Tonight we fought, but it's just those little mistakes that we made in the first couple of periods that obviously was the difference in the game."