Mata caught the England striker with a late lunge in the first half of the clash at the King Power Stadium, with referee Anthony Taylor deciding that a yellow card was sufficient punishment.
The Spain international went on to score United's third goal in what was ultimately a convincing 3-0 victory, with Henrikh Mkhitaryan and Zlatan Ibrahimovic having put Jose Mourinho's side ahead with two goals in the space of 88 first-half seconds.
Mata was delighted with his side's clinical performance but accepted he was perhaps fortunate to have stayed on the pitch.
"I was late, I tried to reach the ball, I didn't want to hurt Jamie," he explained to Sky Sports. "Probably I was a bit lucky but I just wanted to get the ball because I lost it 10 seconds before."
He continued: "I think the performance was quite good. Even before scoring the first goal I think we were trying to control the game through passes and trying to have the ball.
"Mkhi's was an incredible goal and after that we played very good and could have scored twice more. We're very happy because today we took our chances.
"It was very important for Mkhi and me to score because Zlatan is scoring a lot but we need goals from us as well."
Mkhitaryan struck with a powerful run and finish after being moved into a central role behind Ibrahimovic, though he started wide on the left in a 4-4-2 set-up.
"It was something we prepared before the game," Mkhitaryan said. "The manager said 'if it doesn't work with two strikers then we have to change the formation', so that's what we did during the game.
"It's not something that's new for us. We've changed the formation in many games very easily. It worked.
"It's easy to play anywhere. In this game, the manager felt it was better that I play behind the striker. It's his decision and I feel it's correct."