Celtic’s friendly victory over Sligo Rovers last night ended up being a productive exercise that will keep the Bhoys ticking over nicely ahead of their return to Scottish Premiership action. On a night where the Hoops overturned a one-goal deficit, Luis Palma confirmed Celtic’s victory against Sligo Rovers late on, completing his hat-trick in the process. Luke McCowan and Hyunjun Yang also enjoyed a productive evening in the north-west of Ireland. At the same time, Stephen Welsh and Maik Nawrocki both got a full match under their belt despite being bit-part players this term. Brendan Rodgers w…