Celtic’s damaging 2-1 defeat to Celta Vigo has sparked a fierce debate over the officiating after former Hoops midfielder Stiliyan Petrov questioned UEFA’s referee appointment, while Neil Lennon and Hearts defender Craig Halkett also expressed frustration over a disputed first-half incident involving Callum Osmand.

Martin O’Neill’s side entered Thursday’s Europa League encounter desperate for a positive result after losing their opening two matches against Ferencvaros and Benfica. Instead, Celtic suffered a third consecutive European defeat, leaving their qualification hopes under serious pressure.

The controversy centred on an incident in the first half when Osmand appeared to be pushed from behind by Celta defender Javi Rueda as the young forward advanced towards the penalty area. Referee Georgi Kabakov waved away Celtic’s appeals, and no foul was awarded.

The decision left Celtic players and supporters furious. Petrov, speaking on TNT Sports, questioned why the officials had failed to penalise the contact, while Lennon argued that the incident should have resulted in either a penalty or a free-kick.

Yet the disputed call was only part of Celtic’s problems. After Mika Baur gave the hosts the lead in the 47th minute, Javi Rodríguez scored twice in three minutes to turn the match around and leave O’Neill facing difficult questions about his team’s European performances.

STILIYAN PETROV QUESTIONS UEFA’S REFEREE APPOINTMENT

Petrov was particularly critical of the decision not to award a foul when Osmand went down under pressure from Rueda.

The former Celtic midfielder questioned the consistency of the officiating and raised concerns about Kabakov’s experience, arguing that matches of this importance demand officials capable of making decisive calls under pressure.

Petrov said during the broadcast that he could not understand how the referee had failed to recognise the contact. He also suggested that officials should have considered whether the incident warranted a more serious disciplinary response.

His comments added fuel to an already heated debate among Celtic supporters, many of whom believed their team had been denied a promising opportunity to attack.

However, questions about a referee’s experience do not, by themselves, establish that the appointment was inappropriate. Nor does criticism from former players constitute an official finding that the referee made an incorrect decision.

The key issue is whether the contact on Osmand met the criteria for a foul and, if so, where the infringement occurred.

That distinction matters because a foul outside the penalty area would normally result in a free-kick rather than a penalty. A red card would require separate consideration of the circumstances, including whether the incident denied an obvious goalscoring opportunity.

Petrov’s frustration was clear, but the precise disciplinary outcome remains a matter for the applicable rules and the evidence available to the match officials.

NEIL LENNON DELIVERS A BLUNT VERDICT ON THE OSAMND INCIDENT

Petrov was not alone in questioning the decision.

Former Celtic manager Neil Lennon also expressed disbelief that Osmand’s appeals had been dismissed.

Lennon argued that the referee should have awarded a free-kick if he believed the contact occurred outside the penalty area. From his perspective, the forward was moving towards a dangerous position and the contact appeared to affect his progress.

That argument highlights the central frustration surrounding the incident: Celtic felt they should have received a decision, even if the officials believed the infringement occurred just outside the box.

The location of the contact is important. A penalty and a free-kick outside the area carry different consequences, but either could have given Celtic an opportunity to create a dangerous situation.

Instead, play continued, and Camilo Durán was booked for protesting.

The decision quickly became one of the most controversial moments of the evening, particularly because Celtic were still searching for the opening goal.

Nevertheless, it is important to separate what the pundits believed they saw from an independently confirmed explanation of the referee’s decision.

CRAIG HALKETT ALSO BELIEVES CELTIC HAD REASON TO COMPLAIN

Hearts defender Craig Halkett, who was also part of the broadcast discussion, shared the view that there appeared to be meaningful contact on Osmand.

Halkett suggested that Rueda was fortunate to escape punishment, arguing that the contact affected the Celtic forward as he attempted to advance towards goal.

The agreement between Petrov, Lennon and Halkett ensured that the incident received considerable attention after the match.

When several experienced football figures question the same decision, it naturally intensifies scrutiny. Supporters want to understand why their team did not receive a foul, particularly when the incident occurs in a potentially dangerous position.

However, agreement among pundits is not the same as an official ruling that the referee was wrong.

The fairest conclusion is that the incident was sufficiently contentious to provoke strong criticism from multiple observers. Without a definitive explanation from the relevant officials, claims that Celtic were deliberately disadvantaged or definitively robbed would go beyond the available evidence.

COULD THE OSAMND DECISION HAVE CHANGED THE MATCH?

Celtic supporters will understandably wonder what might have happened if the referee had awarded the foul.

A penalty would have offered the hosts a major opportunity to take the lead. A free-kick outside the area could also have created an attacking opportunity, depending on its location and the players available to take it.

But football rarely offers certainty about hypothetical situations.

Even if Celtic had received the decision, there would have been no guarantee that they would have scored or won the match.

What can be said is that the incident occurred during a crucial stage of the first half, when Celtic were attempting to build momentum after surviving Celta Vigo’s early pressure.

A favourable decision might have helped the hosts gain confidence and put their opponents under greater pressure.

Instead, Celtic went into half-time level at 0-0, with the controversy becoming another source of frustration for the home supporters.

The incident deserves scrutiny, but it should not overshadow everything that happened afterwards.

CELTIC TOOK THE LEAD BUT FAILED TO PROTECT IT

Celtic finally found the breakthrough shortly after the restart.

Mika Baur scored in the 47th minute after Haissem Hassan drove down the right and delivered a dangerous ball into the penalty area. The ball broke kindly for Baur, who finished to give the hosts a 1-0 advantage.

For a brief period, Celtic looked capable of securing the result they desperately needed.

Liam Scales then came close to doubling the lead, directing a header against the crossbar from another Hassan delivery.

That missed opportunity proved significant because Celta Vigo subsequently found their way back into the match.

Javi Rodríguez equalised in the 68th minute with a header from a free-kick delivered by Hugo Álvarez. Three minutes later, Rodríguez struck again, this time finding the net with a powerful effort from outside the area.

Suddenly, Celtic had gone from leading to trailing.

The rapid turnaround exposed a familiar weakness in their European campaign: the inability to maintain control when a match becomes uncomfortable.

O’Neill can reasonably question the officiating, but his team must also examine why it allowed Celta to score twice in such a short period.

MARTIN O’NEILL FACES BIGGER QUESTIONS THAN REFEREEING

The disputed Osmand incident may dominate the immediate reaction, but Celtic’s broader European struggles are becoming increasingly difficult to ignore.

Three consecutive defeats mean that the Scottish side have little room for further mistakes if they are to remain in contention for progression.

The contrast between Celtic’s domestic form and their European performances is particularly concerning. A team capable of producing impressive results at home must find a way to translate that confidence into continental competition.

That requires more than attacking quality.

Celtic must improve their defensive concentration, manage transitions more effectively and respond calmly when opponents score. The quick succession of Rodríguez’s goals suggests that the team struggled to regain its organisation after conceding the equaliser.

European matches often turn on small details, but successful teams limit the damage when things go against them.

Celtic had the advantage and a chance to extend it. When the equaliser arrived, they needed to slow the game down and prevent Celta from building further momentum.

Instead, the visitors capitalised on the opportunity.

That is the problem O’Neill must address, regardless of what the officials did or did not get right.

WHAT THE CONTROVERSY MEANS FOR CELTIC’S EUROPA LEAGUE CAMPAIGN

The result leaves Celtic under mounting pressure in the league phase.

Their opening defeats had already made Thursday’s fixture important, and losing again has made the route towards qualification considerably more difficult.

Celtic now need to collect points in their remaining matches while improving performances at both ends of the pitch.

The upcoming European fixtures will test O’Neill’s ability to restore confidence and make tactical adjustments. His players must demonstrate that they can handle pressure without allowing frustration to affect their decision-making.

The manager will also need to ensure that the team takes full advantage of its opportunities. Scales’ header striking the crossbar was an unfortunate moment, but Celtic cannot afford to rely on luck when their European campaign is at stake.

The penalty controversy may remain a talking point among supporters, yet future results will depend on Celtic’s ability to defend leads, create chances and remain composed in difficult situations.

CELTIC FANS DESERVE ANSWERS, BUT THE TEAM MUST RESPOND

The reaction from Petrov, Lennon and Halkett reflects the strength of feeling surrounding the Osmand incident.

Their criticism has placed the decision under the spotlight and renewed questions about consistency in European officiating.

Celtic supporters are entitled to debate whether their team should have received a foul or penalty. It is also reasonable to expect clear explanations when major decisions generate widespread confusion.

But the club cannot allow the controversy to become an excuse for ignoring its own shortcomings.

Celtic were ahead against Celta Vigo and had an opportunity to secure a valuable victory. Within minutes of conceding, they had lost the lead and ultimately the match.

That collapse is a warning sign that needs to be taken seriously.

The Osmand incident deserves scrutiny, but Celtic’s European season will not be rescued by arguments about refereeing alone. O’Neill must find a way to turn frustration into a response on the pitch before another European opportunity slips away.