Why can Hearts 'enjoy build-up' to Celtic showdown?

"With a bit of luck, they can finish second this season".

Excited Heart of Midlothian fans might view that as downplaying their chances considering Saturday's 3-0 win in Kilmarnock lifted Derek McInnes' side five points clear of Celtic at the top of the Scottish Premiership.

But, while the former Kilmarnock boss himself insisted "no-one is getting carried away" with thoughts of challenging for the title, one of his predecessors as head coach, Steven Naismith, was at least willing to go as far as to suggest they could split the Old Firm.

Celtic will be favourites to narrow the gap again after they visit struggling Dundee on Sunday, but what Hearts' victory at Rugby Park has done is ensure they will go into their next game, which happens to be at home to the reigning champions, at least two points clear.

Combined with managerless Rangers being held to a draw at home to Dundee United, it also means Hearts are already 13 points ahead of the side who would have been expected to be Celtic's main challengers.

So how have Hearts managed to make such an impressive start?

Bolstered by investment from Tony Bloom and the Brighton & Hove Albion owner's football analytics division, McInnes was able to overhaul the squad inherited from Neil Critchley and the results are stark.

They have won 11 of their 13 games in all competitions this season, their only defeat coming after a penalty shoot-out against St Mirren in the Premier Sports Cup.

With 19 goals in eight league games, Hearts have scored five more goals than the next most prolific side, Dundee United.

They have also had the highest number of goal attempts, the most on target and the highest conversion rate, with only Celtic having a slightly higher expected goals rate.

Hearts have found the net at least once in all eight league games - more than any other team in the Premiership this season.

Individually, a double against Kilmarnock for Claudio Braga, their summer signing from Aalesunds, means he is joint top scorer with five along with United winger Ivan Dolcek.

Meanwhile, winger Alexandros Kyziridis has four assists in the Premiership this season - more than any other player - since arriving from equally unfashionable Slovak club Zemplin Michalovce.

At the other end of the park, only bottom side Livingston have won more duels, while Hearts are level with Celtic with most clean sheets - five - albeit having played one more game.

Indeed, going four straight games - and 471 minutes - without conceding is their longest run since seven games between December and January 2018.

Braga, a forward remember, and midfielder Cammy Devlin are both in the top four for winning duels, while former Union Berlin goalkeeper Alexander Schwolow has yet to concede a goal since joining the club.

No wonder the Hearts fans - their numbers swelling to nearly 4000 travelling to Ayrshire - unfurled a banner saying: "In Dell we trust."

While "really pleased" with the win at "a notoriously hard venue", McInnes himself was quick to point out to BBC Scotland: "For people who didn't watch the game and see the scoreline and think it was all straightforward, it was far from that.

"I thought Kilmarnock started the first 15-20 minutes the better side.

"I thought we were guilty of giving away too many fouls and not looking after the first pass, poor with our clearances and invited a bit of pressure."

However, he thought that his team settled after Craig Halkett's opener and thought Braga and fellow striker Lawrence Shankland "linked the play brilliantly and dovetailed brilliantly" after he encouraged his side to be "less frantic" after the break.

"I think Lawrence has seven in all competitions as well, so we are getting plenty of goals," McInnes said.

"I think there is that burden off him a wee bit and sharing the load. With the deliveries we've got at set plays, both inswingers and outswingers and the size and aggression we've got, we should be thinking about scoring more goals.

"I am enjoying watching the team, but there's still loads of room for improvement and it's important we recognise that."

McInnes had no plans to watch Celtic in person on Sunday and says "we can be a bit satisfied with our work".

"The Celtic game will take care of itself in terms of the motivation and the atmosphere in the build-up," he said.

"They will be the team to test us the most and we've got to be ready for it."

Naismith thinks Hearts are growing stronger week after week.

"Earlier in the season, the results Hearts were getting were not from big performances," he said.

"There were mistakes in there, Motherwell played them off the park for 60 minutes, so they were winning in different ways.

"But the last few performances, the derby game wasn't a pleasant watch, but their performances are becoming more complete.

"Their forward players make the right choices at the right times and that's what happened tonight for the second and third goal.

This was not a 3-0 game on performances. It was individual mistakes and poor quality which led to giving Hearts opportunities that they snatched out the hands of Kilmarnock."

Naismith pointed to the depth of squad available to McInnes.

"When the window shut you maybe thought the squad is too big, but I don't think you could get a better manager to manage that," he said.

"I think guys are coming off the bench and they're hungry and the guys on the pitch are showing 'I'm not coming out the team'. The real change is they have match winners in their team."

What of the suggestion Hearts are now at least favourites to finish second?

"I wouldn't say they are favourites, but with a bit of luck they can finish second this season," Naismith said.

"In coming seasons, it will be a three-horse race.

"As the seasons go on, they will progressively get further away from the best of the rest and that gap will continue to close.

"The signings they are making are guys who are untapped who are minimum risk because the data backing that. They also have the fan base to grow with it. That's why it's such an exciting time."

What possibility a title challenge this season?

"If they get to January and they are still in the mix, they may have reinforcements to come in," Naismith added.

"Then, if it gets to March time and they are right in the mix, the pressure all pushes away from Hearts and totally on to the Old Firm because there is an expectation that they come first and second."