Celtic ominously moved four points clear in the Scottish Premiership after an astonishing goal spree humiliated last season's runners-up - and this term's putative title rivals - Hearts in Glasgow.

The defending champions found the net seven times, running riot in a first half in which they scored five, hit a post and drew two fine saves from bewildered visiting goalkeeper Beau Reus.

Forward Callum Osmand celebrated his first Celtic start with a quickfire double to put Martin O'Neill's men four goals up inside 40 minutes in front of a raucous, disbelieving Parkhead crowd.

Disbelieving because they had watched their team abjectly lose four of their past five, most recently against Benfica in Lisbon on Thursday.

Hearts were accommodating visitors for a team needing a confidence boost, though. Their failure to deal with two early corners allowed Kieran Tierney to claim his first of the season and Benjamin Nygren his seventh.

The Tynecastle side's defending in the first period was truly calamitous, summed up by a failure to keep out Mika Baur's effort just before half-time. The German showed lovely skill and composure to waltz through before Stephen Kingsley's attempted goalline clearance rebounded off Jamie McCart and rolled apologetically in.

Celtic's fifth and referee David Dickinson had yet to blow for the interval.

Laurent Mendy's fine, curling effort had briefly reduced Hearts' deficit to three but, given Reus's heroics to keep out Nygren, added to the fact Haissem Hassan had smacked a lovely shot off the keeper's right-hand post, a four-goal advantage at the break didn't flatter Celtic at all.

It became five within four minutes of the restart when Camilo Duran gave a flowing move the first-time finish it deserved. And Nygren slammed in a seventh late on to complete the rout.

This was total domination from Celtic against a strangely hapless Hearts, who didn't really make their hosts work particularly hard for the majority of the riches they gleefully plundered.

A statement win for O'Neill's league leaders. A sobering defeat for new Hearts boss Wouter Vrancken, who's likely to remember his first visit to Celtic Park as much as he'll be desperate to forget it.

As starts to games go, scoring twice in the first 10 minutes is pretty much ideal. When you then hit a post seven minutes later, the direction of travel is fairly clear.

If Celtic were under orders to blow Hearts away early, the instruction was carried out to the letter. And then some.

They were 4-0 up inside 40 minutes, 5-1 up at the break, 6-1 in front inside 50 minutes. Had Beau Reus not made a telling stop to deny Nygren an early double, this could have been even more mortifying for the men in maroon.

This was O'Neill's men at their ruthless best, an echo of last season's run to the title when they won their last seven in the league, including that unforgettable final day, championship-sealing win over Hearts.

If they can keep up this appetite in front of goal, their four-point advantage won't be easy for Rangers - or anyone else - to overhaul.

Hearts came into this one on a bit of a roll. Just one defeat in 13 in all competitions. More goals scored in the Premiership than anyone else.

That momentum melted within the first 10 minutes in the cauldron of Parkhead.

A failure to defend corner kicks was their undoing initially, losing two goals from Celtic's first three set-pieces.

To then concede a further three before the break is unforgiveable, especially if you have designs on presenting the big Glasgow two with a genuine title challenge.

Hearts will not do that if the defending witnessed at Celtic Park resurfaces again at any point further down the road.

They'll look to write this one off as a bad day at the office. Very, very bad. Given they had conceded six by the 50th minute, the one blessing is perhaps that it didn't end up worse than 7-1.

Celtic manager Martin O'Neill: "I thought we played really well, really well in the game. Once we got a goal, players got a lot of confidence from that and we carried it on throughout the 90 minutes, so it was a really good performance from us.

"It was nice to win, it was nice to win in the manner in which we did as well - scored some really great goals. We looked really good going forward. Defensively, I thought the back four did exceptionally well."

Hearts head coach Wouter Vrancken: "Really disappointing and also the way it happened. Two set plays killed our game at the start of the game. All of their goals even, when I go back, individual mistakes and then it's difficult to win a game.

"In the set play moments, you have to be on top of your toes, you have to be on front foot to attack the ball there. Against individual mistakes, you can't do too much actually."