He established himself at centre for Edinburgh Reivers. Mayer moved to Leeds from Bristol in 2001, he stayed for one season and scored six tries in the 12 games that he played. Mayer made his debut against Bath and scored his first try against Pontypridd. A strong runner and powerful defender he was hoping to establish himself and Leeds in the top flight and also regain his position in the Scottish international ranks. Mayer's first season ended unhappily with him sustaining a severe hamstring injury just as he was beginning to cement a starting spot in the team and running into some form and a few tries. He struggled with fitness and suffered with injuries leading him to give up professional rugby where upon he returned to Watsonians to see out the remainder of his playing years.