Celtic prepared for the Old Firm Scottish Cup tie with their biggest Premiership win of the season as they routed Livingston at home.

James Forrest and David Turnbull netted to reward first-half dominance.

A Jack Fitzwater own goal, a Mohamed Elyounoussi double and a late Ryan Christie finish sealed a convincing victory as Livingston capitulated.

There was an injury concern for Celtic as Forrest was forced off on his first league start since September.

Fifth-place Livingston remain four points clear of St Johnstone after a first defeat in three Premiership outings.

Having lost the league title to Rangers this season, Scottish Cup holders Celtic face Steven Gerrard's side in the last 16 next Saturday.

Celtic's disappointing season hinges on the trip to Ibrox, with their last chance of silverware at stake.

And interim manager John Kennedy's men impressively took a grip of proceedings as Livingston's early spark faded.

Celtic's first effort on goal produced the opener on the half-hour. Forrest latched on to Odsonne Edouard's lofted pass over the defence to poke a finish beyond Robby McCrorie and inside the near post.

Elyounoussi glanced a header wide from Jonjoe Kenny's cross before turning provider. Greg Taylor released the Norwegian down the left and he hit the byeline to deliver a cross that took a deflection before dropping to Turnbull all alone to tap into the empty net.

Edouard was denied a goal by McCrorie's legs before Livingston manager David Martindale made a double change at half-time - Josh Mullin and Matej Poplatnik on for Jay Emmanuel-Thomas and Craig Sibbald - in a bid to turn the tide.

But the floodgates had opened and Scott Brown's diving header from a corner bounced off the unsuspecting Fitzwater to make it 3-0.

The overworked McCrorie was doing his best to keep the scoreline respectable amid a barrage of shots, but was helpless as Elyounoussi curled a superb strike into the far corner of the net.

Celtic's joy was tempered as Forrest, in just his fourth appearance after a long-term ankle injury, limped off. Kennedy later explained the Scotland winger was withdrawn when he "felt his back stiffen up".

The goals kept coming and the fifth was made in Norway as Kristoffer Ajer galloped forward from defence before playing in compatriot Elyounoussi to dink the ball over McCrorie.

Livingston's miserable day was compounded when former Celtic defender Efe Ambrose sent a pass across his penalty box straight to Christie who accepted the invitation to tuck the ball home.

Man of the match - Mohamed Elyounoussi

What did they say?

Celtic interim manager John Kennedy: "Once we found our groove we were always going to carry a threat. I'm just focusing on the team and how we can improve week on week. I think we're seeing that in the performances now.

"Confidence is huge in football and the players have had a tough time this year. We've tried to rebuild that."

Livingston manager David Martindale: "As bad as we were, Celtic were fantastic. That's not a get-out for us. It's probably the worst we've played in my seven years at this club.

"I've told the players in no uncertain terms it's not good enough. We were all terrible today."
What's next?

Both sides are in Scottish Cup last-16 action next weekend. Celtic face Rangers away on Saturday (16:00) while Livingston take on Aberdeen at Pittodrie the following afternoon (14:00).