Ruapehu remained unbeaten and rose to the top of the premier table with a 53-7 thrashing of Border in Ohakune on Saturday.
McCarthy's Ruapehu romped home, scoring eight tries to Border's one in a one-sided affair.
The bonus points the side have amassed put Ruapehu on 15 points, two in front of Pirates, the only other unbeaten side in the Tasman Tanning Wanganui premier rugby competition.
Ruapehu romped clear in the second spell, piling on 43 unanswered points after leading narrowly 10-7 at the break.
While the scoreline suggested a complete dominance over Border by his side, Ruapehu co-coach Andrew Evans was a happier man in the second half as his forwards took control.