But it almost all unraveled for the Lightning in a disastrous start to the game.
Midway through the second period, Tampa Bay found itself behind 4-1 to the team with the most points in the Western Conference. It would have been pretty easy for the Lightning to pack it in and look ahead to their home game Thursday against Detroit.
Instead, they produced one of the most thrilling comeback victories - and one of the most important - of not just this season but all-time in franchise history.
So how'd they do it? What changed after falling behind 4-1?
Breaking down a big two points gained in 3 Things we learned from a comeback against Chicago.
Video: CHI@TBL: Drouin pots PPG for his second of the game
1. COMEBACK KIDS
The Lightning were expecting to take Chicago's best shot early in Monday's game. The Blackhawks were embarrassed two nights earlier in Sunrise, falling 7-0 to the Florida Panthers. The Bolts knew Chicago would come out to put that miserable result out of their memory.
For 30 minutes, the Blackhawks were successful.
A Chicago push right from the opening face-off saw Artemi Panarin score just 1:23 into the game. After Ondrej Palat leveled the score midway through the first on a power-play goal, Chicago answered less than a minute later and was up 3-1 by the first intermission.
Richard Panik scored at 8:47 of the second period to make it 4-1 Chicago, and the Lightning were teetering on the edge of being knocked out.
But they didn't fall to the canvas.
"You get a left hook here and an uppercut here, but the guys won't go down," Lightning coach Jon Cooper said. "You look at a two month stretch here of a resilient group, this group's showing that right now."
Down by three goals, the Lightning regrouped to play maybe their finest 10-minute stretch of the season. Jonathan Drouin scored a supremely important goal just three minutes after Panik scored to give the Bolts new life and cut the deficit to two.
"If it's 5-1, it's probably out of our hands, but if it's 4-2, then it is a little different game," Drouin said.
Anton Stralman scored 1:02 after Drouin's goal to continue eroding the Blackhawks' lead. With AMALIE Arena now in full throat, Drouin netted his second goal of the period, converting another power play to level the score 4-4.
From there, it was anybody's game. Whichever team wanted it more was going to take home the two points.
Fortunately, the Lightning were the more desperate team and played like it on Monday.
Cooper, though, was quick to put the feel-good win in perspective.
"It's not going to mean anything unless we get ourselves in (the playoffs)," Cooper said of the win. "This was just another step. It's a really exciting one, but just like we had to regroup after the Arizona game, we have to regroup after the Chicago game. We got the two we came for, now it's all about Detroit."
Video: Gourde on scoring OT game winning goal
2. GOOD GOURDE
Even before scoring the overtime game-winner, Yanni Gourde deserved a lot of credit for bringing energy to a Lightning team that was reeling after falling behind 4-1.
Gourde, along with his linemates Adam Erne and Joel Vermin, played at a breakneck speed throughout the entire game. They set a tone early that although they were inexperienced and only a couple months removed from the American Hockey League, they weren't going to be intimidated by the veteran Blackhawks, winners of three of the last seven Stanley Cups.
They played with physicality. They played with pace. And they played with purpose.
Their effort helped steady the Bolts at a time when they were reeling.
And Gourde was the ring leader.
He's been tasked with being an energy guy for the Lightning since being recalled from Syracuse on March 6, and he's performed his role very well.
But, on Monday, Gourde took it to an even greater level.
"He is the road less traveled for sure," Cooper said. "It was not a couple years ago he was playing in the East Coast League. There's a player that a will and a want gets you to where you want to be. He is proving that right now. He plays with energy. He just hounds pucks. He and (Brayden Point) have a lot of similarity in that regard, how they just hound pucks."
When the Bolts scored to make it 4-3, the Erne-Gourde-Vermin line had four or five high-quality chances from in close that they came oh-so-close to converting. It felt like if anybody was going to produce the game-winner from the Lightning, it was going to be someone from that third line.
Gourde was the one to finally break through in overtime.
Coming down the ice on a breakaway after Panarin had the puck poked away in the 3-on-3, Gourde checked his options and shot low to the glove side of Chicago goalie Scott Darling, just trying to make sure he put something on net.
Instead, he beat Darling clean, netting the game-winner for the second goal of his NHL career. His first also came in spectacular fashion, scoring on a shorthanded breakaway March 11 versus Florida, becoming just the fourth Lightning player all-time to score their first career goal in that fashion.
After the game, Gourde was all smiles in the locker room and reflective on what it's taken to reach this point.
"It's a pretty amazing moment," he said. "I've worked very hard to be here. I've worked since a long time ago. Obviously, I was in the (East Coast Hockey League) at a moment in my career. It's very special to be here tonight and be playing along those guys. It's a pretty amazing feeling."
Video: CHI@TBL: Vasilevskiy robs Kane with terrific pad stop
3. VASY DOUBLES BACK
Andrei Vasilevskiy did not look sharp in the first period Monday night. And that was before he gave up three goals on eight shots. The Russian netminder appeared to have trouble tracking the puck, and each Chicago shot produced a juicy rebound as Vasilevskiy was unable to corral the initial attempts.
After giving up a goal to Tomas Jurco at 13:41 of the first period, Cooper pulled Vasilevskiy in favor of Peter Budaj, but the Bolts head coach knew in the back of his mind he would go back to Vasilevskiy later in the game.
"The faith we have in Vasilevskiy is unwavering," Cooper said. "At the time of the game, for me, it was a 'Let's slow this game down. I know we're down 3-1, but there's a lot of time left. We don't want this one to get out of hand.' Not that we're sitting here saying it was Vasilevskiy's doing, but let's get him out, let's take a breath. Buds came in, shut the door the rest of the way. The whole time at the end of the first period in my head I was thinking, 'I'm going to put that kid back in.' Some points as a coach you're going with your gut, and the feeling I have that we're going to win this game. Vasilevskiy's going to win this game for us. He just had to take a six minute break."
Vasilevskiy re-entered to start the second period with a completely different demeanor and newfound level of confidence. Former Bolt Richard Panik scored midway through the second to make it 4-1 Chicago, but Vasilevskiy dug in to deny the Blackhawks over the final 30 minutes and another four-plus minutes in overtime.
"After the first period, I was thinking, 'Damn, that sucked,'" Vasilevskiy said in his matter-of-fact way. "But coach gave me a second chance, and I made a couple saves. The guys played really well and scored five goals against almost the best team in the league."
In the third period with the game tied 4-4, Vasilevskiy made his most important stop of the night, denying Patrick Kane with his right leg pad after Kane got behind the Bolts' defense and had a clear look at goal. Kane entered Monday's game as the league's third leading scorer, but on this particular play, Vasilevskiy was just a little bit better.
That save would prove to be crucial in Tampa Bay's come-from-behind win.
"Patrick Kane pretty much clawed his way to a breakaway, and Vasy made that backdoor save," Cooper said. "In my head I'm thinking, 'Remember that one.' Ultimately, we needed it because the game went to overtime."
After a sub-par start to the game, Vasilevskiy regained his form, and just in time to spur the Bolts' victory.
"It's for sure a confidence booster for me," Vasilevskiy said after the game. "Even after three goals against in the first 12 minutes or something, coach said, 'I'll give you a second chance. Go get them. Go make some saves for us.' As I said, a confidence booster for me."