The gold medal gymnast was in Chicago Sunday to watch Jonathan Owens' Chicago Bears take on the Minnesota Vikings ... and, in a particularly important moment, her man came up with a big stop short of the goal line.

Owens comes up and rips the ball out of running back Aaron Jones' hands ... running off toward the sideline with his prize.

The camera cuts to Simone Biles watching from the box ... and, she's waving her hands like she just doesn't care -- grinning widely after the big moment for JO.

As you know ... Biles and Owens are very supportive of each other's careers -- with Simone becoming a mainstay at the Bears' Soldier Field since Owens joined the team this summer.

Of course, Owens missed a few weeks of practice to go support his girl out in Paris ... where she won multiple gold medals at the 2024 Olympics.

BTW ... Simone's got an all-denim fit on at the game -- not exactly decked out in Bears blue and orange, but at least it's no longer Packers green and white.