Johnson gave Tampa Bay a 1-0 lead when he scored 29 seconds into the game on the first shift. He beat Crawford glove side with a wrist shot from the slot.
"We weren't as sharp as we needed to be on the first shift, and we dug ourselves a hole," Chicago coach Jeremy Colliton said. "I thought Corey gave us a chance to crawl back in the game and make it a game, but you can't chase it and expect to win."
Johnson made it 2-0 at 7:15 after Point set him up for a shot from the top of the crease.
"They were tough to handle," Blackhawks defenseman Duncan Keith said. "They came out hard. They've done that several times this season. We needed to be better. We definitely played better as the game went on."