IT may be just as well that Neil Lennon enjoys being under pressure. The scrutiny on the Celtic manager isn’t about to ease up any time soon on the evidence of yet another damaging defeat at the hands of Sparta Prague.

The fact is that the longer that Celtic show such startling ineptitude in their defending, the harder it gets for Lennon’s remaining supporters to defend him. Celtic have now lost 19 goals in seven games since they last kept a clean sheet in the late win at St Johnstone. They have two wins from their last nine games, in which they have conceded 21 times. And they are out of the Europa League.

That they have lost eight goals in just two games to this distinctly run-of-the-mill Sparta Prague side is verging on a travesty. Lukas Julis has five of those, getting a brace here to add to his Celtic Park hat-trick after David Hancko had cancelled out Odsonne Edouard’s early opener. Srdan Plavsic rubbed salt into Celtic’s wounds by making it 4-1 in stoppage time.

It had all looked so good for Celtic early on, with the brilliance of Edouard’s goal suggesting something of a turning point for both the forward and his team. By the end though it was a familiar tale of woe with the Celtic attack blunted and the defence in total disarray.

There were four changes to the Celtic line-up from the one that drew with Hibernian on Saturday, as Christopher Jullien made his return to the line-up for the first time since September and Hatem Elhamed came in to stiffen up the right-hand side at the expense of Jeremie Frimpong. At least that was the theory. No matter the personnel deployed by Lennon at the back, the same frailties remain.

Further up the pitch Olivier Ntcham replaced Tom Rogic, while Edouard was in for Albian Ajeti at the sharp end of the attack.

You might have thought that Celtic would have taken note of the way that David Moberg Karlsson called the tune when Sparta ransacked Celtic Park, but he was given the freedom of the pitch early on as he flashed a shot just wide before setting up a great headed opportunity that was spurned by Andreas Vindheim.

Celtic were looking for a spark, and boy did Edouard provide it. The visitors countered with pace and precision as Moi Elyounoussi slipped the ball into the path of Edouard’s perfectly timed run in behind. He faced up Hancko, chopped this way and that, tied him up in knots then produced a smart finish across Florin Nita and in off the post.

Unfortunately, Celtic’s set-piece Achilles’ heel was their undoing once more as the hosts levelled just before the half hour.

A corner was swung in that was headed up in the air by Jullien, and with every Celtic player apart from Callum McGregor running out to the ball, David Pavelka sclaffed the ball back into the area. The lone deep Celtic man played three Sparta players onside, and Hancko untied his legs from the pasting he took from Edouard just in time to slam home from close range.

Celtic responded, and a deep cross from Elhamed sat up beautifully for Ntcham at the back post, but the midfielder sliced wide from a great position.

Alas, Celtic’s woeful defending cost them once more as Sparta turned it around. The visiting backline made a hearty meal out of a simple bread and butter cross, allowing a low ball from the right by Barek Dockal to travel right across the six-yard line for Julis to tap home from a couple of yards.

It could have been worse just before the break, and what do you know, it was another set-piece that cut Celtic to ribbons. Diego Laxalt gave away a cheap foul on the edge of the area, Dockal swung in a cross and Ladislav Krejci had the freedom of Prague to plant a header off Scott Bain’s right-hand post.

Celtic emerged from the tunnel knowing that both they and their manager needed a huge second-half performance, and they almost got off to a flyer as Edouard’s free-kick from the edge of the area was kept out brilliantly by Nita low to his right.

Christie had been anonymous in the first half out wide, but he started to edge his way into a central area, winning the free-kick that Edouard struck before curling a trademark effort just wide of the far post.

Celtic probed and waited for their chance, and when it came, it fell to the right man. Edouard though got his finish all wrong. An exchange between the forward and Ntcham saw him presented with the ball eight yards from goal, but he scuffed the ball harmlessly into the hands of Nita.

Rogic was thrown on for Brown as Lennon went for broke, but a period of pressure came to nothing, and with 10 minutes to go came the sucker punch.

Elhamed failed to cut out a pass forward to Karlsson, and Sparta’s deadly duo struck again as Karlsson crossed for the unmarked Julis to volley home. How could it get any worse for Celtic? Well, in injury-time, it did.

A long ball saw Plavsic round Bain and hold off McGregor to seal a scarcely believable 4-1 double over the Scottish champions.

It brought the curtain down on a wretched European campaign for Celtic and then some. Domestic matters may be the priority, but they have a hell of a battle on to salvage their season if recent evidence is anything to go by.