The 28-year-old shared the sizzling photos on Instagram as it was revealed she has joined as a 2024 rookie ahead of the magazine's May edition.
Brittany looks incredible in the saucy snaps, wearing a red halter-neck one-piece – no doubt a nod to her husband's team, the Kansas City Chiefs – that leaves little to the imagination.
The Mulger swimsuit exposes Brittany's toned stomach and chest thanks to a huge cut-out down the center that plunges below her navel.
Her sculpted legs look incredibly long in the high-cut design which also shows a hint of her toned derriere.
To complete her beach look, the former athlete rocks textured waves in her blonde hair, glossy pink lips, and bronzed skin from head to toe.
Sharing a behind-the-scenes video from the shoot in Belize, Brittany can also be seen posing in several tiny red bikinis that highlight her incredible physique.
Describing the shoot, which you can see below, as being "unapologetically herself", Brittany admitted she "never in a million years" would have imagined she would be gracing the pages of the iconic Sports Illustrated Swimsuit edition.
"I'm truly just so humbled and still in disbelief," she told the publication.
"As a girl from Tyler, Texas, who only really knew sports, never in a million years did I think I'd be in the SI Swimsuit Issue. I'm just so grateful for this opportunity," she added.
Explaining why she said 'yes' to the opportunity, Brittany said: "I want women to feel empowered to always be yourself, love yourself and feel confident in whatever you do, and I think SI Swimsuit does, too."
She continued: "Be confident in who you are and be unapologetically yourself. People are going to love you or hate you, but finding your values and what makes you the best version of yourself is what really matters.
"'I want people to know they can accomplish anything, even things you never thought would be possible in your wildest dreams."
Her husband showed his appreciation for the photos, sharing grabs of the sultry shoot alongside three heart-eyes emojis on his Story.
The couple are currently in Las Vegas ahead of Sunday's Super Bowl, which will see the Chiefs go against the San Francisco 49ers in a battle for the championship title.
Brittany and Patrick – who share two children – are high-school sweethearts and married in 2022 in Hawaii.
On her big day, Brittany walked down the aisle in a stunning custom Versace gown complete with rippled folds of fabric, a giant bow, and intricate crystal detailing.
In March 2023, she marked their first anniversary with a series of throwback photos from their special day.
In her caption, she gushed: "Happy 1st Anniversary. One of the best weeks of my life, marrying your best friend it's one of the greatest things you could do!
"Nothing beats doing life with you and these beautiful kiddos of ours! Year 1 was wild but we got many more to go. You & Me forever."
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