He is No. 15 on the squad and No. 1 in her heart.

Brittany Mahomes supported husband Patrick at the Kansas City Chiefs’ game against the Los Angeles Chargers on Sunday, wearing not one, but two accessories with his jersey number.

The soon-to-be mother of three, 29, stuck to SoFi Stadium guidelines with her clear Stoney Clover Lane fanny pack ($108), an additional $47.

Mahomes chose a simple red t-shirt and a “Mahomes 15” cap to complete the casual look.

The personal trainer showed off her pre-game look on her Instagram Story and captioned it, “Game Day Girlie.”

She kept it simple for the first few games of the season, opting last week for a rhinestone-studded NFL Shop Chiefs T-shirt ($58) with Vitality biker shorts ($62) and knee-high red cowboy boots.

And for the season opener against the Baltimore Ravens on September 5, she paired cargo jeans from Alice + Olivia with a simple white T-shirt.

However, the Sports Illustrated swimsuit model was thrust into the spotlight on September 15 to mark Patrick’s 29th birthday.

She watched the Chiefs beat the Cincinnati Bengals at Arrowhead Stadium in a full Chanel look, which included a black logo minidress and loafers, before changing into a striped halter dress by Givenchy for a party at the couple’s residence .

The party, held at her palatial Kansas City mansion, included oversized balloons, cups with baby photos of the quarterback, a DJ and a photo booth.

Taylor Swift was in attendance – as was Travis Kelce, who gave the birthday boy a five-figure Louis Vuitton golf bag.

Mahomes and Swift are close friends but have yet to sit together at an NFL game this year, despite a whirlwind weekend in NYC that included a US Open outing and dinner.