Maguire said he meant no disrespect to Sunderland supporters after celebrating the opening goal of his hat-trick in front of the dugout.
The attacking midfielder told Sky Sports that his reaction was based on the frustrating end to his career at the club.
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"It was a build-up of things,” Maguire said.
"I thought I was hard done by in my time here - it didn’t end the way I wanted to. I got a yellow card early on, and I looked over he was trying to get me sent off.
“It worked in the favour of us - because at the end of the day he’s been sent up the tunnel.
“I can’t tell you what I said but I think I did my talking on the pitch. It was just a bit of tongue in cheek for my last 6 months here. It ended badly for me.
“I hope the Sunderland fans are okay with me. I was getting booed but I’ve got nothing but admiration and respect for them. I loved my time here. I wasn’t meaning to be disrespectful to them at all. I hope they can see from my point of view the way it ended for me here.”
But ex-Sunderland player Stephen Elliott hit out at Maguire.
Speaking on Twitter, he said: “Really poor #SAFC. Lack of urgency & ball is being moved far too slow. Still should be level. Better needed 2nd half. Maguire a good player who did well for Sunderland but to celebrate like that in an oppositions managers face (no matter what went on between pair) is classless.”
In his post-match press conference, Johnson said of the celebration: "It’s not for me to comment.
“You'd have to ask him. When you're manager you pick a team, you don't hold grudges and players sometimes move on, it's part of the game.
“For me, you pick players, Embleton, Pritchard, based on your belief in them.
“Good luck to Chris, to be honest, my focus is on the team.”