January Jones poses in deeply plunging zip-up and ripped jeans and leaves famous friends stunned

January Jones turned a Saturday at home in Los Angeles into a red-hot fashion moment with a new at-home photo session she shared on Instagram.

The California-based actress highlighted her support for her home basketball team, the Los Angeles Clippers, with her latest fit.

She wore a bright red zip-up top – the zip pulled generously low to turn it into a plunging moment – with the striking garment tucked into a pair of ripped black jeans.

“Your new @laclippers referee, brb gotta go get my whistle,” January joked in her caption. Topped off with a light red lip and her gold chain (with a pendant in the shape of a key), the eye-catching ensemble and her trim physique certainly caught the attention of her famous friends.

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Charlize Theron simply commented: “Damn,” with a flame emoji, a sentiment echoed by Christina Ricci also writing: “Girrrl damn.”

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A fan gushed: “Aging backwards, giving late 90s Cosmo vibes, ice in your eyes, and you’re just playing. This is how you drip……”

Another wrote: “This isn’t gonna work out, the players will be too distracted…,” while a third added: “This is possibly the greatest thing ever posted on Instagram.”

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January shares her LA home with her son, Xander, 11, who rarely makes appearances on her social feed. The actress has never revealed the identity of his father, admitting her purpose in life as a single mom is to “provide stability” for her son.

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In a candid interview with Red magazine about her motherhood journey, the Golden Globe nominee revealed it’s only been her and Xander from the beginning.

“It’s good to have strong women around a man to teach him to respect…