That's it for a long day in the Scottish Premiership.

Hearts' lead is down to two points after that loss in Ayrshire, while Celtic came from behind to beat Motherwell 3-1.

Join us for a lunchtime kick-off in Paisley, with managerless St Mirren hosting Rangers, then it's up to Dundee for a derby at Dens Park.

Hearts head coach Derek McInnes tells BBC Scotland: "It wasn't good enough. I didn’t think we started the game well, for whatever reason.

"We had a good week’s work going into this game. I thought we had a good warm-up, looked sharp and ready then and when you come away from home against a team fighting for their lives you know what to expect.

"I didn’t think we looked sharp enough to the pitch off the ball, didn’t close spaces down or stop crosses. I just thought we looked easy to play against.

"They get far too simplistic a goal and there’s no pressure on the cross and they have a free man in the box.

"We gave Kilmarnock something to cling on to and you have to credit them.

"We had 60% possession and more chances but we huffed and puffed and you have to say Kilmarnock scrapped and fought for the three points.

"We tried to throw more attacking players on it but it petered out really. We’re disappointed, not with our effort, but the quality of our play.

"I’ve told the players we still wake up tomorrow top of the league with eight games to go. We pick ourselves up and go again."

Image source, SNS

Hearts boss Derek McInnes is disappointed as he tells BBC Scotland: "I thought we just looked too easy to play against in the first half."

We'll hear more from him in just a moment.

Cammy Bell
Former Kilmarnock goalkeeper on BBC Sportsound

Hearts are not going to go away. It's going to be a brilliant end to the season.

Allan Preston
Former Hearts midfielder on BBC Sportsound

There's still a lot of football to be played, and a lot of twists and turns.

We've got a Dundee derby at Dens Park at 14:00.

Before that, it's St Mirren v Rangers at 12:00.

If Rangers win that one, they'll be three points behind Hearts.

Kilmarnock manager Neil McCann tells BBC Scotland: "There's a lot to like. I'm so proud of the players. We've had two weeks to dwell on the Falkirk result.

"The message was to play with risk and bravery, but that we would have to match Hearts.

"We knew they would throw balls in the box and be physical, but to a man we were outstanding and thoroughly deserved the three points.

"We did all the stuff off the ball so well. Derek [McInnes] is a first-class manager and we had to adjust our tactics to respect how Hearts would play.

"We had everything tonight and could have scored more as well. We tried to stay composed, they stuck their chests out and deserve their victory.

"The bar was set when we came in - what we expect as a coaching team. What we're doing at home is so pleasing. I want it to become a fortress."

Image source, SNS

That's three wins from four at home for Killie.

They join St Mirren on 24 points and have bottom side Livingston at Rugby Park next.

Will they avoid the tension of a relegation play-off?

What next for Hearts?

The league leaders' pre-split fixtures are Dundee (H), Livingston (A), Motherwell (H).

Hearts fans might be feeling a bit glum but the Edinburgh side are still sitting top of the pile after 30 games.

Derek McInnes is sure to emphasise that fact.

Allan Preston
Former Hearts midfielder on BBC Sportsound

Marc Leonard gave the ball away straight from kick off and that epitomised the whole evening for Hearts. They were misplacing passes, the ball was rolling under feet, not enough energy.

Cammy Bell
Former Kilmarnock goalkeeper on BBC Sportsound

The best way for Kilmarnock to defend is to get at teams and that's what they did.

I haven't seen much of Hearts this season and I was really disappointed. They didn't offer anything. Kilmarnock were by far the better team.

Derek McInnes applauds the large travelling support at Rugby Park before disappearing down the tunnel.

Meanwhile, home boss Neil McCann is virtually doing a lap of honour, skipping across the pitch sporting a huge smile.

Allan Preston
Former Hearts defender on BBC Sportsound

Hearts have been really poor, but you have to give Kilmarnock credit, they have been terrific from the first minute.

That's three away defeats in a row for Hearts as their lead at the top of the Scottish Premiership is cut down to two points.

A massive win for Kilmarnock, who move nine points in front of bottom side Livingston.

Image source, SNS

'Ole, Ole' shout the Killie fans as the ball is kept in the corner with a few fancy flicks thrown in.

Kilmarnock are trying to run down the clock and a stupid foul from Islam Chesnokov is just what they want.