Dave O’Callaghan looking over his shoulder

Dave O’Callaghan is only 25, but with a ready supply of youngsters coming through the Munster system he’s already beginning to feel old.

Last weekend, 18-year-old Bill Johnston made his first start for the province in the win over London Irish and his ability to mix it against a physically daunting opposition suggests it’s only a matter of time before he makes his competitive debut.

As O’Callaghan prepares for tomorrow night’s Guinness Pro12 opener against Treviso at Musgrave Park (7.45), he took time out to talk about Johnston.