Ange Postecoglou endured a horrendous pre-Champions League jolt as his brittle young backline were torn to shreds by West Ham in a 6-2 thrashing.

The Aussie coach is way short of defensive options heading into Wednesday’s return leg against FC Midtjylland due to a lack of available signings, injuries and suspensions.

Kids Stephen Welsh and Dane Murray were the central pairing who finished the 1-1 midweek draw against the Danes after Nir Bitton’s red card.

Postecoglou may have to go with the duo again with Anthony Ralston at right-back and the trio all started against the Hammers.

However, David Moyes’ Londoners carved through the Hoops defence with ease as they bagged six goals at Celtic Park.

Callum McGregor and Ryan Christie netted at the beginning of each half, but the floodgates opened at the other end with alarming ease.

Michail Antonio scored twice and won a penalty that Mark Noble struck home before Said Benrahma, Jarrod Bowen and ex-Hoops kid Armstrong Oko-Flex rained goals past both Vasilis Barkas and his half-time replacement Scott Bain.

It was a brutal sight for Postecoglou who somehow needs to find a formula to solidify his team ahead of Wednesday’s clash and the big Premiership kick-off next weekend.

Celtic were ripped apart at times and the start belied the harsh truths which would follow.

McGregor thieved possession from Manuel Lanzini and ignored the driving run of Christie into the box to curl home an eighth-minute opener.

However, by the interval, Postecoglou’s backline had shipped three down the other end.

Murray’s pass out from the back was sloppy and picked off allowing Antonio to show sublime feet to ease away from defenders and Barkas to slot an equaliser.

Welsh and Murray were then left treading water when Ralston lost possession and a sweeping counter-attack sent the Hammers hitman scampering clear of the central defensive duo.

Barkas left a big hole at his near post for the attacker to hit and he did so with customary aplomb.

The striker was causing havoc and, when referee John Beaton adjudged him to have been tripped in the box just before half-time by Ismaila Soro, Moyes’ captain Noble sent the Greek keeper the wrong way from the penalty spot.

Barkas was replaced for the second period by Bain and Celtic reduced the deficit when Liel Abada’s dangerous cross was prodded over the line by Christie.

Hopes of a fightback didn’t last long as yet another rapid counter attack ripped Celtic’s young backline to pieces and Benrahma calmly sidestepped Bain to roll home.

Postecoglou immediately replaced all 10 outfield players at that stage to rest them ahead of the trip to Denmark.

Most were welcomed, but boos greeted the arrival of Leigh Griffiths from a section of the crowd after recent off-field events.

The sub was also hounded by some when taking set plays as others showed support and attempted to drown out the catcalls with applause.

It was West Ham who were applauding 15 minutes from time when Bowen escaped the new Celtic rearguard including Nir Bitton to knock home his team’s fifth.

Still the pain wasn’t over for the Aussie boss as Armstrong Oko-Flex, who left Parkhead to move to the Hammers a month ago, angled a sixth goal across Bain and into the bottom corner.

Postecoglou stood, arms folded staring sternly. He somehow needs to find solutions. And find them quickly.

3 talking points

Backline headaches

Celtic’s young centre-back Murray is just starting out in his top-team career after making a debut five days previously against FC Midtjylland and the examination from Antonio will have taught him some harsh and valuable lessons. The teenager was easily turned by the burly striker early doors and a slack pass led to the hitman levelling the game. Antonio then left him and partner Welsh in his wake to score a second.

The ease in which the backline was again picked off on the counter attack for the fourth West Ham goal must have worried Postecoglou as much as the fans inside Celtic Park.

On the front foot

With defensive issues going into the Champions League game, Postecoglou may need his attacking weapons to outscore the hosts in Denmark. Some of Christie’s touches were sublime and he was deserving of his goal.

Abada, who struck in the first leg against Midtjylland, provided it with a splendid cross and the sight of James Forrest as his replacement offered more encouragement. However, Odsonne Edouard needs to find his spark. He missed a golden opportunity to head home from close range in the first period and struggled to engineer much for himself.

Bark in the firing line

Postecoglou gave Barkas another chance in goal and the Greek initially responded with two excellent one-on-one saves from Antonio and Bowen inside the opening 10 minutes. However, although he had no chance with the striker’s first, he left a gaping hole at his near post for the attacker to hit for his second and he obliged. Bain had no chance with either of the first two goals he lost and he also made a couple of stops. But he also looked sluggish getting across to Oko-Flex’s shot for the sixth goal. Postecoglou faces a big call in Denmark.

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