Fit health 54 year old male

Fit health 54 year old male.
No medication or medical conditions.
No resent stress
No history of psoriasis or eczema
Rash appeared on lower leg 2 months ago. No other part of body involved.
Has had a course of antibiotics from GP which have had no effect.
Is this fungal

I would say that it has a scaly leading edge similar to tinea. I would take a fungal scraping, treat as tinea, and if it doesn’t get better, biopsy. I suppose Bowen’s disease or mycosis fungoides is a possibility.