Taylor Swift is all in for her boo Travis Kelce’s new NFL “Era” … because she just showed up in style to cheer him on as the Chiefs face off against the Ravens in the season opener.

The singer’s on break from her epic tour, so she’s showing love and support for Travis and his team as they kick off another winning season Thursday night in Kansas City … and she arrived about an hour before kickoff.

Taylor pulled up to Arrowhead Stadium in a denim outfit … with red boots rising all the way up past her knees, plus a cute little purse.

It’s been a year since Taylor first appeared at a Chiefs game, and her impact was a game-changer — she even roped in new fans for the team with her star power.

Taylor attended some games with Kelce’s mom, Donna — and who could forget that fairytale Superbowl kiss that had the whole world talking?

In fact, Taylor’s such a pro now that Travis confirmed she’s even helping draw up Chiefs plays!