The Londoners won the home fixture 2-0, with second-half goals from Mile Jedinak and Campbell taking the tie beyond the reach of the dominant Foxes.
However, the result was misleading, with the performance a tough fought battle between the two sides, especially with Nigel Pearson’s men controlling the game in the first-half.
But a quick start to the second period, with Campbell opening the scoring on the 51st minute, paved the way to victory, and it was all but confirmed three minutes later.
And in the aftermath of the game, Campbell, who started his career at Manchester United, revealed that it was some tough words from Eagles manager Neil Warnock that catalysed the team into claiming all three points.
Speaking to London24, the 27-year-old forward admitted that he was not performing well, and used Warnock’s advice to put more effort in for the good of the entire team - effort that was rewarded with his second goal of the season.
He said: “At half-time I went in and held my hands up and I knew I was poor in the first half.
“Sometimes when your touch is not as great, you’ve just got to run around and that was basically it, to put myself about more, cause them more problems and it seemed to work.
“The manager said I needed to be more lively so I came out in the second half and it helps when the lads behind me are closing people down a lot quicker.
“I think we managed that a lot better in the second half and created more chances.”
The result took Palace to four games without defeat - all under the tutelage of recently appointed Warnock - winning the last two, and Campbell was delighted to have finally recorded back-to-back wins that took the Eagles into the top 10 in the Premier League table.
“I am delighted to score again but more importantly back-to-back wins for the team. The fans are brilliant so it was great to get my first goal at the home stadium, but more importantly we got the three points and won the game,” he continued.
“Football is always more enjoyable when you’re scoring and winning games.”