"The second and third period, I was like, 'Geez, just don't get hurt,'" the Boston Bruins defenseman said. "I just wanted to play in the playoffs so bad."
Carlo, who is in his third NHL season, was unable to play in the Stanley Cup Playoffs in each of his first two seasons because of injuries, a concussion in 2017 and a broken leg last year.
He figured he wasn't going to play in the regular-season finale against the Tampa Bay Lightning on April 6, but he still had to get through the game at Minnesota, and the fear of getting injured again days before the start of the playoffs was real and haunting.
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"Seeing the energy, the physicality, everything you've wanted to be a part of so bad and dreamed about for your whole life is right there in front of you, and you can't touch it," Carlo said. "It was tough."
Carlo made it through in Minnesota, getting an assist in 21:01 of ice time in a 3-0 win, and in the past six and a half weeks, he's made up for lost time.
He's the only regular in the lineup who hasn't scored a goal in the playoffs, but the 22-year-old is a big reason why the Bruins are in the Stanley Cup Final. Game 1 against either the St. Louis Blues or San Jose Sharks will be at TD Garden on May 27 (8 p.m. ET; NBC, SN, CBC, TVAS).
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The Blues lead the Sharks 3-2 and can advance to the Cup Final with a win in Game 6 of the Western Conference Final at Enterprise Center on Tuesday (8 p.m. ET; NBCSN, CBC, TVAS).
"This is what we've seen out of Brandon in the regular season for a long time, (a) steady, solid defensive player, good penalty killer, reliable," Boston coach Bruce Cassidy said. "With the bigger stage you always wonder, but he's passed the test so far."
Carlo is arguably the most unheralded player for Boston. Although he hasn't ended up on the scoresheet much (two assists in 17 games) and is hardly ever talked about after the game because his play isn't headline-grabbing, he just keeps doing his job well.
He is averaging 22:16 of ice time per game in the playoffs, third behind Charlie McAvoy (24:20) and Zdeno Chara (22:32), who make up Boston's top defense pair. Carlo, who plays on the second pair with Torey Krug, is also plus-6 with 21 blocked shots and only four penalty minutes. He averages a team-high 3:24 per game on the penalty kill; he has played 57 seconds total on the power play.
"The experience has made me a better player just for the confidence side of things, knowing I can play at this level, the highest level with the fastest pace," Carlo said. "This is the hardest time of the year and it's something you don't really know if you can do it until you go through it, so going through it and trying to play as best as I can and handling myself has been huge for my confidence and growing as a player.
"I think like I'm establishing myself more as that shutdown defenseman."
Carlo's best performances have come at the most important times, including Games 6 and 7 against the Toronto Maple Leafs in the first round with the Bruins trailing the series 3-2.
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He played 23:41 and had four takeaways, a block, two hits and two shots in a 4-2 win in Game 6 on April 21. Two nights later, he played 24:04 and was a plus-2 with four shots, three blocks and a takeaway in a 5-1 win in Game 7.
In Boston's series-clinching 3-0 win against the Columbus Blue Jackets in Game 6 of the second round, Carlo played 24:14, including 5:57 shorthanded, and was plus-2 with four shots and a block.
When Chara missed Game 4 against the Carolina Hurricanes in the Eastern Conference Final because of an undisclosed injury, Carlo stepped up and played 23:28 with two blocks, two hits and a takeaway in a 4-0 win at PNC Arena that sent the Bruins to the Stanley Cup Final.
"A guy like Brandon Carlo probably doesn't get enough credit because he's not on the scoresheet on the regular," Bruins forward David Backes said. "But he's 6-foot-5, he moves like a deer out there, he's tough to play against, he's got a long stick and he's relentless."
In many respects, Carlo is the Bruins' younger version of Chara.
Although he can only dream right now of having the same type of career as the future Hall of Famer, it's not a coincidence the Bruins paired Carlo with Chara when he was a rookie in the 2016-17 season.
It was an apprenticeship that gave Carlo hands-on research for how to play as a big man in the NHL.
"Who better, right?" Cassidy said. "One is 6-5 and the other 6-9."
Carlo learned how to have the mindset of being a shutdown defenseman from Chara.
"I know Zee had talked to me about that, about Carlo playing against top players every night, to relish that," Cassidy said. "So we're playing Tampa, you've got [Steven] Stamkos, [Nikita] Kucherov tonight. Here's how we're going to frustrate them, this is what they like to do. I think that was the first thing Zee taught Brandon, to have the mindset to relish and watch guys get frustrated if they don't get their offensive chances."
You do that with technique, battling in front of the net, boxing out, getting your stick under their stick instead of on top of it, Cassidy said. Chara showed Carlo all of it.
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"He's always huge on positioning on the ice, just giving yourself the best opportunity to keep those guys to the outside," Carlo said. "And communication on the ice is the biggest thing I learned from him. He was always telling me to be the loudest guy."
Last season, Carlo moved to the second pair to play alongside Krug, the 5-9 dynamic offensive defenseman. It was Cassidy's way of saying Carlo's apprenticeship was over, that he didn't need Chara by his side anymore, that he was ready to be on his own.
"I think he's second to none on our team in eliminating plays and eliminating the other team's cycle," Krug said. "I know where he is at all times. If I have a reckless D partner, then I can get in trouble sometimes. It's nice to have his consistency. He's always in the right spot."
Cassidy said he likes Krug and Carlo together because they can make up the difference in what might be lacking in the other's game.
"Brandon, if his game gets away from him a little bit, it's usually with the puck, his puck decision, or he gets nervous with it, loses confidence, however you want to phrase it or categorize that, and Torey is a calming influence on him in that regard," Cassidy said. "Brandon can cover a lot of ice, so if Torey is on the offensive side of things, Brandon is pretty reliable thinking defense first."
He's so defensive that it's become a bit of a running joke that Carlo is the only Bruins' regular who hasn't scored a goal yet in the playoffs.
Nineteen other Boston players have scored at least one, tying its record from 1988 for the most in a single postseason, but Carlo had only two goals in 72 regular-season games and has eight in 247 NHL games (including playoffs).
"The whole goal-scoring thing isn't my forte," Carlo said. "Maybe I'll slide an [empty-net goal] in."
That he still can is key. Not having the opportunity to do anything in the playoffs in his first two seasons tested Carlo.
"Faith is a big thing for me, and I kept that," Carlo said. "Hopefully, it'll be worth it in the end."
NHL.com staff writer Amalie Benjamin contributed to this story