Miranda Lambert made a surprise appearance in Las Vegas on Friday and looked every inch the country star cowgirl.MORE: Miranda Lambert inundated with messages and well wishes following heartfelt messageThe 38-year-old wore blue denim jeans that hugged her curves and a bright orange shirt tied at the waist with white fringe paired with a cowboy hat as she joined George Strait on stage for a duet of his hit Run.WATCH: Miranda Lambert shares surprising news about CMA performanceWalking out to