As well as the overnight pre-season win over DC United in the first fixture of the US Tour, there was another update for the Celtic fans they probably don’t want to hear about. The future of Matt O’Riley has been the subject of intense speculation this summer as some of England’s and Europe’s top clubs circle the Celtic midfielder. With Atalanta’s interest grabbing much of the headlines this week, Juventus have also been named as a club who have an eye on him as well. Well, it seems that the interest in O’Riley could be about to ramp up again after the latest update from The Mirror. Southampto…