The Cleveland Browns grounds crew rushed to plant new grass right after Machine Gun Kelly's homecoming concert at FirstEnergy Stadium on Saturday ... but it wasn't because the show got too rowdy -- TMZ Sports is told it was all part of the plan.
The Cleveland native played in front of a packed crowd this past Saturday ... giving a bloody performance that even included zip-lining throughout the stadium.
There's just one thing that had people concerned -- Cleveland hosts the Philadelphia Eagles for a preseason game on Sunday .