It is still up to coach's discretion as to who participates at the varsity level. I know there are wrestle offs, but the right to challenge is up to the coach's rules.
As an example, a 2 way football starter missed the 4 days of practice prior to school starting and was not allowed to suit up for the 1st game. The coach was notified well in advance and the reason for missing was the athlete was out-of-town at Philmont Scout Ranch hiking over 70 miles through the mountains (conditioning) and then to pass his Eagle Scout Board of Review.
