Giordano is pitted against his Pacific Division rival Brent Burns of the San Jose Sharks and reigning champ Victor Hedman of the Presidents' Trophy-winning Tampa Bay Lightning.
Monahan, meanwhile, looks to become the fourth player in franchise history to bring home the Lady Byng Trophy, which is given to the "player voted to best combine sportsmanship, gentlemanly conduct and ability."
Florida Panthers captain Aleksander Barkov and St. Louis Blues pivot and recently crowned Conn Smythe winner, Ryan O'Reilly, are his two challengers.
Joe Mullen (1987, 1989), Jiri Hudler (2015) and Johnny Gaudreau (2017) are the other Flames to have brought home the award.
This weekend, we're taking a closer look at each nominee and making a case for why 'Gio' and 'Mony' should take home the hardware.
Today, we cover the captain, Mark Giordano:
Video: Mark Giordano has been absolutely dominant in 2018-19
He broke records.
Brought down the house.
But to fully appreciate Giordano and the staggering impact he had on the division-winning Flames, one look at the stat column shows why the captain should be the frontrunner for the Norris.
He finished the year second among defencemen with 17 goals and 74 points in 78 regular-season games, had a league-leading four short-handed markers, 21 powerplay points and a league-best +39 rating, all while logging more minutes (1,890:39 or 24:14 per game) than any other Flame.
Video: CGY@NJD: Giordano walks in and scores on the backhand
Giordano, whose 833 regular-season games rank second in franchise history, is just the fifth blueliner in league history to score 60 or more points at age 35, joining Ray Bourque, Nick Lidstrom, Al MacInnis and Sergei Zubov.
This was - by far - the most prolific of Gio's 12 NHL campaigns, doubling his output from the previous two years and setting new career benchmarks in all but one offensive metric - goals (he scored 21 in 2015-16).
"I'm not dumb to the fact that I'm getting older here," Giordano said on locker clean-out day back in April. "The key, I think, to sustaining a high level of play, is to understand that. Don't fight it. Work with it.
"I'm going to be 36 when we drop the puck next year. But I don't feel that way at all. I feel like I'm coming off a year where I played my best hockey. Some might think that would take a toll over the course of - probably - 90-plus games when you factor in the pre-season …
"I don't feel that way at all. I want to keep going.
"This is the best I've ever felt, physically."
The points are one thing.
A fraction of the overall picture, you might argue.
But what Giordano excelled at the most this past year was his ability to defend, then chug that Father Time-defying motor of his and transition the puck into attack mode.
Among defencemen with 400-plus minutes of ice time, Giordano was the NHL's top possession driver in the final half season, scoring a Corsi-For percentage of 59.42 - more than three percentage points higher than fellow finalist Brent Burns - and doing so while having only a 46.28% offensive zone start percentage.
Burns, meanwhile, started a whopping 64.55% of his shifts in the offensive zone, while Hedman - who clocked in with a 51.08% Corsi (49th of the 128 players to qualify, based on minutes) - had 52.33% start at the friendly end of the ice.
So, despite the untenable role of playing No.-1 minutes and hushing the opponent's top weapons, Gio thrived and took over the game like no other offensively.
Scoring chances were again in the captain's favour, with the Flame generating 58.14% of the regular chances and 57.14% of the high-danger variety, 5-on-5, to grade third and 13th in both categories among D men.
Burns ranked 47th at 51.52%, and 36th at 53.40%, respectively.
Hedman, again, brings up the rear at 50.25% and 49.01% - both squarely in the bottom third of the league rankings.
All combined, Giordano's impeccable, two-way play helped the Flames tighten up defensively and finish with the second-best goal differential at plus-66.
Who better to enlighten us on both the player and person than those the captain serves in your city, year-round?
Indeed, Gio does more than just dominate on the ice.
He's the pace.
And has had the most meaningful and everlasting impact on both the Flames locker-room and the very fabric of the C of Red, at large.
"In the locker-room, I sit right next to him and everybody listens up and stops talking when he says something," reports Matthew Tkachuk, who is one of a long list of Flames players to laud the captain as the team's Mr. 'Everything.'
"The way he's able to get a grasp a room; the way he's able to relate to everybody. It's very, very impressive."
Travis Hamonic agreed, adding Gio should be a shoo-in for both the Norris and Messier.
"Everything," Hamonic said when asked what the captain means to this team. "I've been saying for a long time - he's the best defenceman in the game, and he's got to be the best leader.
"He's an incredible person, on and off the ice. You guys see it all year, what he does on the ice. In practices. In games. The season he had, that's crazy. He just means that much to our group, our team, this organization, the city. He's 'Mr. Everything' for us. That's the probably best way to describe someone and what they mean is calling them Mr. Everything."
In truth, it's an easy one.
Only three other players have won the Norris Trophy at age 35 or older: Lidstrom, who did it four times between ages 35 and 40; former Flames icon MacInnis (but as a member of the St. Louis Blues), and Doug Harvey.
They were the crème de la crème.
The elite of their time.
Come Wednesday, the whole hockey world will hopefully know it.
The do-it-all, leave-it-all-out-there, heart-and-soul captain of the Flames should become just the eighth undrafted player in league history - and the first since Bobby Orr in 1974-75 - to be awarded the illustrious title of Norris Trophy champion.
No one deserves it more.