Taylor Swift ran into a tech issue while performing night 1 of her concerts in Indianapolis, Indiana … but the superstar did not miss a beat — literally.

Here’s the deal … while rockin’ the Lucas Oil Stadium Friday, it appeared Taylor’s in-ear monitors ran out of juice … and video shows a crew member dashing out to swap batteries as TS belted “Lavender Haze.”

Some thought that perhaps it was a mic issue, but that seemed to be working just fine … and she was holding onto her IEM during the quick switch.

Needless to say … fans roared as soon as they realized something was happening, but TS was not going to allow it to ruin the moment.

After it was done … Taylor thanked the crew member — who got their own round of applause — and continued jamming on as if nothing was wrong.

TS is finishing the US portion of her tour on Sunday in Indy … then officially finishes her “Eras” tour in Vancouver on December 8.