Assignment No 1 among his August engagements was to keep the lid on Martin O'Neill, Leicester's jack-in-the-box manager, as third official at the opening-day match with Aston Villa at Filbert Street.
Then came Derby's notorious first game at their new Pride Park stadium, where the Sheffield official was the man forced to abandon proceedings as red-faced officials struggled in vain to rectify one of the more embarrassing instances of floodlight failure.
The 36-year-old leisure centre manager inevitably came in for some sharp criticism for his decision to call the match off, especially given that the stadium was fully illuminated by the time it was announced, albeit by emergency lighting that itself later gave out.
He will be cheered, then, to have been given unsolicited praise by the Crystal Palace manager, Steve Coppell, for his handling of Saturday's contest at Leeds. Despite seeing four of his players booked, Coppell insisted Rennie had an excellent match.
"He tried to play advantage wherever possible and to sort out problems with a quiet word first rather than reaching straight for the yellow card," Coppell said.
Rennie, born in Jamaica but a Sheffield boy from the age of six, believes in a philosophy of conciliation rather than confrontation.
"Refereeing is not just about interpreting the rules, it's the use of life skills," he said in a recent interview. "I see myself as an arbitrator. I'm not there to trip players up. I'll explain a decision when asked. They may not agree and know my word is final, but it helps to create an empathy."Reuse content