Like McKenna, Martyn Pert and Lee Grant, his assistant manager and first-team coach, are also former United coaches.
“There are quite a lot of staff and players in the different departments,” he said. “I'm not fantastic at keeping in touch when I'm working in a job, I have to say. I'm pretty much 100 per cent focused on where I'm currently at.
“But there are some great people there and some really good relationships, and I've had lots of nice messages over the last couple of years as we've had our landmarks and our successes over the last couple of years right up to last weekend, and nice messages from people at the club.
“So, there's still communication there with many people and I'm sure we'll see some familiar and friendly faces on Sunday and it would be good to catch up after the game.
“I know certainly on my side, and Martyn and Lee and Axel (Tuanzebe) and other people here who have got previous history at that club, and the people on their side who know us will equally be fighting for their performance and their opportunity to get points on Sunday.”
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