Taylor Swift rocks vintage '90s Chiefs sweatshirt before slipping into sexy all-black look as she cheers on boyfriend Travis Kelce at Buffalo Bills game in Kansas City

Taylor Swift cheered on her boyfriend Travis Kelce on Sunday during the Kansas City Chiefs vs. the Buffalo Bills game at Arrowhead Stadium in Kansas City.

And for the big showdown, the pop superstar, 33, rocked two looks which included a vintage '90s red-and-black Chiefs sweatshirt from local Kansas City retailer Westside Storey, as per People.

The sweatshirt features a large Chiefs logo along the front, as well as on the shoulders. 

And it appears that the songstress helped the store swiftly sell out of the garment, as the $250 sweatshirt is no longer available on the store's website. 

The Bad Blood hitmaker paired the red and black look with her signature red lipstick, and was seen cheering the athlete, 34, from a suite. 

Unfortunately, despite Taylor's cheers, the Chiefs ended up losing, with a final score of 20 - 17 for the Bills. 

Swift went through a rollercoaster of emotions watching Kelce and his Kansas City Chiefs take on the opposing team.

Later, Swift was caught holding hands with Kelce as they exited the stadium.

Instead of her sweater, the Anti-Hero hitmaker slipped into a sexy all-black look that featured a faux leather miniskirt that showed off her legs.

She styled it with a low-cut bodysuit with silver details and an oversized coat that stopped mid-calf.

She looked absolutely smitten with the tight end as the photo showed her gazing in his direction as they strolled together. 

The singer hot-footed it from New York City on Sunday morning and arrived in time to watch Kelce for a sixth time this season, once again sitting alongside his family from a VIP suite at Arrowhead Stadium.

She went through a range of emotions as she watched her man put his body on the line - looking downcast as the Chiefs fell behind in the first half, before jumping to her feet as Kelce made some big plays to pull the home team back level.

Swift's latest visit to Kansas City comes just days before her 34th birthday, and at the end of a historic week in which she was named TIME Magazine's Person of the Year.

The pop superstar seemingly can't get enough of the NFL this season - especially now that the South American leg of her Eras tour is finished - after she traveled to Lambeau Field last week as her beau and the Chiefs fell to the Green Bay Packers.

As she arrived at Arrowhead for Kelce's latest game on Sunday, she waved at fans who called out to her as she got on a golf cart to be driven into the venue.

The singer is on a break from her massively successful Eras tour until February after recently performing across Argentina and Brazil.

This week, she spoke to TIME Magazine for an interview alongside her big award, opening up about the attention she gets when she goes to cheer on Travis.

'I don’t know how they know what suite I’m in,' she said. 'There’s a camera, like, a half-mile away, and you don’t know where it is, and you have no idea when the-camera is putting you in the broadcast, so I don’t know if I’m being shown 17 times or once.

'I’m just there to support Travis. I have no awareness of if I’m being shown too much and p****ng off a few dads, Brads, and Chads.'

She was also spotted with a group of celebrity friends on a girl's night out to dinner at Lucali in Brooklyn on Friday night.

She was joined by Selena Gomez, Zoe Kravitz and Cara Delevigne for the occasion.

It comes following news that Kelce is reportedly planning a surprise party for Swift's birthday next week, and there are suggestions the NFL star could even propose.

Taylor turns 34 on Wednesday, December 13 and her whirlwind romance with the Kansas City Chiefs star has taken the world by storm since they went public back in September.

DailyMail.com exclusively reported that pop star Swift was moving in to Kelce's stunning $6million mansion in Kansas City after returning from her South America Eras tour in November, a signal of how well things have gone between the pair.

And now, a bombshell report in Life and Style claims the Chiefs star is pulling out all of the stops for her birthday next week.

The publication quotes an insider as saying: 'They already know they're compatible, but living together for an extended period will be the ultimate test.'

'Even Taylor and Travis are surprised at how seamlessly they've been able to blend their lives. It's been effortless. '

And as for her birthday celebrations, the insider was quoted as saying: 'Travis has something special planned.

'He's arranged a very intimate romantic dinner just for the two of them, and is also trying to pull off a semi-surprise party with the help of some of her closest friends.

'There are whispers that he could use the opportunity to propose — that's what everyone, including Taylor, is hoping for!'

After Swift and Kelce went public with their relationship through her attending his game against the Chicago Bears on September 24, the NFL player said he felt happier than when he won the Super Bowl in February.

'As all the attention comes, it feels like, you know - I was on top of the world after the Super Bowl and right now even more on top of the world now,' he said at the start of October.

It is not known precisely when Kelce and Swift started dating - she confirmed in an interview with TIME this week that they were a couple when she showed up to the Bears game that day.

'By the time I went to that first game, we were a couple. We would never be psychotic enough to hard launch a first date,' Swift said.