By the end of last season, going to Celtic Park would have held few fears for Hearts.

They won there in December for the first time in 14 years - the only Scottish side to do so all campaign - and added another home win over Celtic later in the term.

But Saturday's trip has a completely different feel to it for Steven Naismith's side after six straight defeats and exits from the Scottish League Cup and Europa League.

And with only two goals scored so far - from an expected goals rating of 4.1 - last season's Premiership third force have issues to address at both ends of the pitch.

So, what has gone wrong for Naismith's team?

Former Hibernian, Motherwell and Rangers winger Jamie Murphy is well versed in both Scottish top-flight football and the Edinburgh dynamic.

"It's just been a terrible start to the season for them in the league," Murphy told the BBC's Scottish Football podcast.

"Sometimes European games distract you a little bit. You can see the same at Kilmarnock.

"Six losses in a row is something that clubs usually look at and start thinking about maybe something changing. But Naismith is good manager, he knows the game."

Another former Hibs favourite, Scott Allan, feels last season's top scorer Lawrence Shankland's dip in form is affecting Hearts.

The Scotland forward is yet to score this term having netted 31 goals last season, 21 of them in the league.

Only Kilmarnock and Ross County (2.5%) have a lower conversion rate than Hearts (3.57) in this season's Premiership. Kilmarnock and Hibs (nine) are the only teams with fewer shots on target than Hearts' 11.

That's despite Hearts seeing more of the ball than most of their contemporaries, and their touches in the opposition box is third behind Celtic and Rangers. But it is not producing the openings or the goals they seek.

"I've seen a lot of Hearts," Allan said. "The problem is the games where they maybe didn't play so well last year, Shankland was producing.

"The international week probably [came] at good time. They need to stop the rot. It's as simple as that and that starts from defence usually."

Integrating summer attacking signings Yan Dhanda and Blair Spittal into the right formation has been difficult so far and finding the best blend will be crucial to stopping that rot.

Naismith has been accused of tinkering formation and line-ups too often at the expense of cohesion, with Hearts having made 13 changes to their starting team in the four games so far, the second most in the Premiership, and that's without counting alterations made between League Cup and Europa League matches.

That seems to be affecting the defence as much as it is their attacking output.

Hearts have used two different goalkeepers, a back three, a back five, and a back four, and rotated the personnel across the defence.

It seems to be affecting players' confidence, with two errors already leading directly to goals, more than any other team in the league.

Celtic lost twice to Hearts last season during a transitional phase for Brendan Rodgers' side.

The champions are having no issues so far this term with the sale of Matt O'Riley not yet showing any impact given the form of Reo Hatate, Paulo Bernardo and captain Callum McGregor, not to mention the recent arrivals of Arne Engels and Luke McCowan.

Rodgers' side are yet to concede in the league and have added motivation to perform on Saturday. The following Wednesday, Celtic host Slovan Bratislava in their Champions League opener.

But Hearts too have Europe on their mind, albeit not until next month. The Europa League defeat by Viktoria Plzen meant a Conference League berth for Naismith's team and they play Dinamo Minsk in Azerbaijan in early October.

Hearts have three Premiership games to get into some sort of shape before then. After Saturday, they are away again to St Mirren on 21 September then host Ross County the following Saturday.

The autumn promises to be a challenging period with trips to Aberdeen, Hibs, Rangers and Cercle Brugge all to come before the end of November.

Tynecastle fans looked forward to European and domestic action this season, as Aberdeen supporters did the previous summer.

But it would appear it will take an almighty effort to make the dual endeavour worthwhile.