Philippe Clement accused Celtic counterpart Brendan Rodgers of being "not respectful" ahead of next week's Old Firm derby after Rangers beat Kilmarnock to narrow the gap at the top of the Scottish Premiership to three points.

Rodgers had suggested "next Saturday, we can have a bit of fun" at Celtic Park following his side's 3-0 win over Heart of Midlothian the previous day.

"It’s not really respectful towards my team," Clement responded. "I will never say things like that about an opponent."

However, Rangers' manager added: "I heard yesterday that they are going to have fun. We're going to have fun also."

It looked like a shock result could be on the cards that would have given Celtic the chance to retain the title against their city rivals next weekend when Kilmarnock took an early lead through a James Tavernier own-goal.

Rangers' captain then had a penalty saved, but with Kilmarnock defender Joe Wright sent off for the hand ball that caused the spot kick, Clement's side ended a frenetic game at Ibrox with comfortable win.

Fabio Silva scored on the brink of half-time to level, Ben Davies' rebound put them ahead, before Tom Lawrence and John Souttar added extras to wrap the game up.

"I stepped into the building six months ago when we were seven points behind," Clement said. "It's now three. With a victory next week, it can be zero.

"We need to do what we did in the first two games against Celtic but be more decisive in the moment. Twice, we were close to a result - even at Celtic Park with 10 men. We have all the quality to win."

Even for a Sunday lunchtime kick-off, there was a particularly flat atmosphere at Ibrox after a few weeks in which Rangers' charge for the title has taken several blows.

The opening half hour got pulses racing, but perhaps not the way Rangers' fans would have liked.

There was a VAR check on a Corrie Ndaba handball. David Dickinson came across to have a look, but the referee stuck with his on-field decision of no penalty.

Then John Lundstram had the ball in the back of the net after Cyriel Dessers had gone down in the penalty box.

Dickinson pointed for a penalty, then an offside, then we all waited while VAR Steven Kirkland confirmed that the Nigerian striker was two yards offside.

Kilmarnock scored from their only foray into the Rangers box. A deep, seemingly unthreatening, cross was knocked back towards goal by Matty Kennedy, with the ball hitting Tavernier's arm and bouncing in slow-motion into the goal.

Ibrox was stunned, but there was almost an immediate response. Lundstram picked out Silva, who flicked at goal, but it was blocked on the line.

VAR intervened to show Wright had saved the ball with his arm and Rangers had their 21st penalty of the season.

Wright marched off as Tavernier stepped up, but the Rangers skipper saw his low effort well-saved by goalkeeper Will Dennis. Cue the groans and grumbles.

There seemed to be no way through the Kilmarnock rearguard until the last kick of the first half. Lundstram picked out Silva again and this time the on-loan forward tucked the ball into the corner.

Timing is everything and it let out a lot of the tension around the stands and, probably, in the dressing room. Level at half-time, Rangers came out after the break with all the momentum.

The hosts were relentless in their bombardment of the Kilmarnock goal and eventually went ahead when Lundstram's low drive was spilled by Dennis, with Davies - on at half-time for his first league appearance since October - knocking in from close range.

Rangers made the points safe when another substitute, Lawrence, shimmied on to his right 20 yards out and curled in a fantastic finish.

The hosts' fourth - scored in the 92nd minute - might be crucial to their goal difference as Souttar was on hand after Lawrence's effort from distance was parried into the air by Dennis.

When Wright was sent off, a Rangers' victory felt inevitable - but it took them far longer to take the lead than they would have liked.

With the exception of Lundstram, their attacking players struggled in the first half. Kilmarnock were comfortable to sit in a low-block, wait for the cross to come in, and clear it away.

There was a lack of movement and creativity that worried the Ibrox crowd. Add in Tavernier missing his penalty and the nerves were starting to show.

Silva's goal settled things - although his celebration will rile a few.

The second half was more on script and, although it was far from a vintage performance, they got the job done.

As for Kilmarnock, hard lines. Their plan - steal a goal on the counter and park the bus - worked, briefly. After the red card, it was always going to be an uphill battle.

They can no longer catch Hearts in third, but fourth is almost confirmed and they should be extremely proud of their performances over the campaign.

Rangers manager Philippe Clement: "In a lot of ways, I'm satisfied. It's an important win. Kilmarnock only lost two games from the beginning of December - both against us. It's now three. My boys are the only ones to do that.

"It's about winning but also quality. If you only focus on winning, you lose the quality. We need to do the right things with and without the ball. In many parts of the game, we did."

Kilmarnock manaager Derek McInnes: "A lot of things transpired against us. The scoreline was pretty harsh on us. Early part of the game, we showed what we've been this season. Vassell and Watkins were doing terrific.

"It wasn't as if Rangers were playing through us. It was their directness that was causing us problems."

Rangers travel across Glasgow to face Celtic next Saturday (12:30 BST), while Kilmarnock are hosted by St Mirren (15:00).