It has been a short, sharp shock of a week for Celtic.

Seven days ago the Parkhead side were springing into a new season, unfurling a league flag and aiming for Champions League football.

But this defeat at Tynecastle to a solitary Kyle Lafferty goal seemed in keeping with the tense tone of the week at the club.

The sour discord between the boardroom and dressing room appeared to hang heavy over this game, with Dedryck Boyata’s agent adding another spoon to keep things stirring away.

The representative of the Belgian stopper cited "broken promises" as he added to the sense of disharmony at the club. Boyata's back injury that kept him out of a Friday afternoon training session as well as this game at Tynecastle will raise an eyebrow in the immediate aftermath of the Parkhead side knocking back a £9m bid from Fulham this week.

How Celtic might have done with the Belgian defender. Lafferty enjoyed his goal and milked his celebrations but his fellow forward Uche Ikpeazu was the real handful for Celtic’s backline.

The power of Ikpeazu was something they never quite got to grips with and the way in which he was allowed to bully his way past Jozo Simunovic and Jack Hendry will be a cause of concern as Celtic prepare for the second leg of their third round UEFA Champions League qualifier in Athens on Tuesday night.

Lafferty had given Hearts the lead shortly before the hour mark when he lashed home a low volley from the edge of the box after the Celtic defence seemed to stall for a second.

Ikpeazu’s did the hard work in the build-up before Lafferty finished.

A rally was expected to come from Celtic in the second period but the Parkhead side seemed to struggle to find any real sense of fluency.

Some of that could have been attributed to the changes in personnel ahead of Tuesday's game.

Eboue Kouassi was given a rare start in the middle of the park while Jonny Hayes took up a place on the left flank. Leigh Griffiths lasted an hour – and had one first-half effort booted off the line – while Simunovic and Hendry were at the back with Kristoffer Ajer suspended for the tie in Greece.

Celtic rang the changes in the second period with Odsonne Edouard, James Forrest and Tom Rogic all brought into the fray as the Parkhead side looked to get something out of the game.

Rogic thought he had pulled one back with a curling effort from the edge of the box after Scott Sinclair had worked his way through a packed Hearts defence but his effort was just wide of the target.

The Australian tried his luck from distance on a couple of occasions while Forrest too tried to inject some energy into proceedings.

Mikael Lustig had a chance as the game drew to a close at the back post but he seemed caught in two minds as to whether to header the ball or aim a kick.

It summed up what was a disjointed afternoon for Celtic.