The Foxes triumphed at Loftus Road in the early kick-off, while Danny Wilson and Giuseppe Sannino began their new jobs at Barnsley and Watford with draws
Nigel Pearson's Leicester outfit had lost two and drawn one in the league prior to Tuesday's Capital One Cup exit at the hands of Manchester City, but the Midlands outfit bounced back by claiming all three points at Loftus Road in Saturday's early kick-off.
Forward Jamie Vardy notched the only goal of the game against Harry Redknapp's charges, firing low past Rob Green after collecting David Nugent's flick-on.
QPR's afternoon went from the bad to worse with five minutes remaining as Joey Barton received his marching orders. The midfielder had been booked for a foul on Gary Taylor-Fletcher moments before receiving a second caution for kicking the ball at the same man.
Burnley capitalised on the situation by returning to the top of the league with a hard-fought 2-1 triumph over Paul Ince's Blackpool.
Danny Ings' fine season continued as he opened the scoring to notch his 17th goal in all competitions, but the sides went into half-time level thanks to Craig Cathcart's close-range header on 24 minutes.
Sean Dyche's men were not to be denied, however, as Scott Arfield curled home a superb winner two minutes after the break.
Danny Wilson's second stint as manager of bottom-of-the-league Barnsley began with a 0-0 draw at Yorkshire rivals Leeds United, while new Watford head coach Giuseppe Sannino started life with a 1-1 draw at Ipswich Town, with Troy Deeney rescuing a point after David McGoldrick had put the hosts ahead from the penalty spot.
Derby County's superb run of form continued with a 3-1 victory at home to Doncaster Rovers. Jamie Ward, Simon Dawkins and Craig Bryson all netted as Steve McClaren's men racked up a seventh straight league victory, leaving the promotion candidates in fourth spot.
Fellow promotion contenders Reading succumbed to a 2-1 defeat to Wigan Athletic at the Madejski Stadium, while Nottingham Forest drew a blank in a 0-0 stalemate at Birmingham City.
At the bottom end of the table, relegation threatened Yeovil and Sheffield Wednesday both fell to home defeats. Yeovil lost 1-0 to Blackburn Rovers thanks to Jordan Rhodes' 13th league goal of the season, while Wednesday were beaten 2-1 by Bournemouth.
Elsewhere, Bolton Wanderers came from behind to draw 1-1 with Charlton Athletic, Brighton and Hove Albion were held to a 0-0 draw at home to Huddersfield Town and Middlesbrough ended a run of three matches without a win with a 2-0 success at Millwall.