Merchiston Castle School can secure a brace of titles tonight in the finals of the Brewin Dolphin Scottish Schools Under-18 and Under-16 Cups at BT Murrayfield to cap a hugely successful season for the Colinton school.

Now under the direction of former Edinburgh coach Rob Moffat, Merchiston face defending champions George Watson's College in the under-18 final and Dollar Academy at under-16 level. Merchiston reached the under-18 final with impressive wins over Robert Gordon's College and George Heriot's School in the first two rounds before comfortably defeating Stewart's-Melville College in the semi-final. Merchiston have already beaten Watson's this season too.

Much of Merchiston's play will revolve round their No.8 Zach Mercer, who was at Williamwood High School before taking up a scholarship at Merchiston. Mercer is part of a strong pack expected to deliver possession to a back line in which former Ayr full-back Aaron Tait and winger Louie Tong are pacy finishers.

"It should be a really competitive final," said Moffat. "I have to make sure the boys are calm and that they really enjoy the experience. I suppose a slight concern would be if the boys panicked."

Watson's are aiming for a third successive title and showed their Cup credentials in the semi-final, coming from behind to defeat Strathallan 25-22. "This is a good group of boys, who have done well this season," said Ally Donaldson, the Watson's director of rugby.

In the under-16 final, Dollar will be seeking to rediscover old glories and given their performances this season, the consensus is that the Clackmannanshire school will be favourites.