Martin O’Neill deserves credit for Celtic’s outstanding performance against Hearts, but some of his substitutions during the 2-1 Europa League defeat to Celta Vigo were difficult to understand.

Celtic were chasing an equaliser when O’Neill withdrew Camilo Durán, replaced Mika Baur with Oliver Sørensen and left Alex Oxlade-Chamberlain sitting on the bench.

Martin O’Neill’s decision to remove Camilo Durán was baffling

With Celtic trailing 2-1, O’Neill replaced Durán with Sebastian Tounekti in the 80th minute. It was a strange decision considering the Colombian’s recent form. Durán had scored against Benfica and Hearts, while also providing two assists in the 7-1 demolition of the Edinburgh side.

He had already tested Celta goalkeeper Ionut Radu with a header in the first half and was giving the Spanish defence something to think about with his movement and pace.

Durán wasn’t having his best game, but Celtic needed a goal and O’Neill removed one of his most dangerous attacking players.

Kasper Høgh had entered the action seven minutes earlier, replacing Haissem Hassan. Surely there was an argument for keeping Durán on the pitch alongside the Danish striker?

Instead, O’Neill turned to Tounekti, whose recent performances have done little to suggest he was the man to rescue Celtic’s European campaign.

To be fair to the manager, his options were limited. Jota wasn’t registered in the Europa League squad, Hyunjun Yang was unavailable and Callum Osmand had already been forced off through injury.

However, Tounekti’s struggles at Celtic have been evident for weeks, and the winger was substituted at half-time during the 4-1 defeat to Benfica.

Bringing him on at the expense of an in-form Durán was always going to raise questions.

Alex Oxlade-Chamberlain deserved his chance ahead of Oliver Sørensen

O’Neill’s decision to introduce Sørensen instead of Oxlade-Chamberlain was arguably even more frustrating.

The Danish midfielder replaced Mika Baur in the 79th minute, despite struggling badly during his previous European start against Benfica. Sørensen was largely ineffective in Lisbon and was replaced by Oxlade-Chamberlain in the 57th minute. Celtic looked more settled in midfield after the former Liverpool player entered the action.

Yet, a week later, O’Neill opted for Sørensen again when Celtic desperately needed something different.

Oxlade-Chamberlain has looked composed and assured during his domestic appearances, including another solid cameo against Hearts. His experience and ability to carry the ball through midfield offered O’Neill a different option.

Sørensen, meanwhile, continues to get opportunities in Europe despite failing to make much of an impression in these matches. There is also the question of removing Baur, Celtic’s goalscorer against Celta Vigo, when the team was already struggling to create chances.

No one can guarantee that Oxlade-Chamberlain would have changed the result, but his performances had certainly earned him an opportunity.

Celtic managed just eight shots compared to Celta Vigo’s 22, which shows how much the home side struggled against their Spanish opponents.

O’Neill cannot take all the blame for another European defeat. The players were second best for long spells and Celta Vigo deserved their victory.

But Celtic were only one goal behind with ten minutes remaining. Taking Durán off, turning to Sørensen after his Benfica struggles and leaving Oxlade-Chamberlain unused were decisions that made an already difficult task even harder.