With the dust from last night’s Europa League encounter at Celtic Park having just about settled, the time for soul-searching on the part of the Scottish champions has begun. Valencia were always the favourites for this game, but a palpable sense of optimism could be felt in Parkhead during the buildup to kick-off. It continued shortly thereafter, too; Celtic started the game positively, and looked as if they were capable of going toe-to-toe with their Spanish opposition.

Disappointingly - and somewhat predictably, perhaps - a particularly passive and ponderous display from Celtic resulted in what was ultimately a fairly comfortable night for Marcelino’s side. This isn’t the first time this has happened on Brendan Rodgers’ watch, either. Far too often, it seems, Celtic go into a European encounter as underdogs with a decent chance of at least putting up some sort of resistance, and then deliver a simply underwhelming display.

Rodgers deserves his fair share of the blame here. For large spells of the game, even when Celtic were two goals down, the defence were happy to pass the ball between themselves, shifting the ball from left to right and right to left, looking for an opening that never materialised. This slow, uninspiring build-up play may well reap rewards domestically, but Valencia were far too organised defensively to be troubled by this approach.

READ MORE: How the Celtic players rated in the Europa League encounter

This is where Celtic let themselves down against Valencia time and time again and tactically speaking, they looked miles behind their Spanish opponents. Celtic were determined to maintain possession in defence and refused to take risks going forward, and were shut out by the well-drilled Spaniards accordingly. Celtic nominally had an extra man in midifield, given the flat 4-4-2 formation Marcelino fielded, but very rarely, if ever, did they press home this numerical advantage.

The Herald:

The visitors were prepared to sit deep and catch out Celtic on the break if and when the opportunity arose. Marcelino set up his side in a zonal marking system, with the two forwards dropping deep when out of possession, and Celtic simply couldn’t find any gaps. Each of the four-man Celtic defence consistently stayed behind the ball and when Scott Brown dropped back in order to distribute the ball to his team-mates, the Valencia players vastly outnumbered the Celtic attackers, leaving no space on the pitch for the home side to move into.

Both Jeremy Toljan and Emilio Izaguirre had poor games on Thursday evening and their inability to contribute to the Celtic attack by pushing beyond the Valencia wingers ultimately resulted in the Celtic forwards being severely outnumbered in possession. Izaguirre, in particular, had a fairly torrid time deputising in Kieran Tierney’s absence. The Honduran looked uncomfortable in possession and a liability out of it; diving in rashly, mis-timing his tackles or simply failing to track his runner. As the game wore on, Valencia were getting more and more joy down the left side of the Celtic defence as Izaguirre offered little-to-no resistance.

READ MORE: Five things we learned as Spaniards show Europa League class

Celtic did look better once Timo Weah and Odsonne Edouard came on for the final half-hour, with the latter looking like Celtic’s best option going forward. But even with the tactical re-jig these changes encouraged, Celtic remained too cautious going forward to seriously trouble the Spaniards.

The Herald:

Towards the end of the game, James Forrest started getting some luck down the right-hand side, taking his opposite number on and finding space to dart into behind him. But when he arrived at the edge of the box looking to pick out a man, there was only ever one or two players to aim for in a crowded Valencia box. Even at two goals down, Celtic rarely committed to attacking with any sort of conviction and any half-chances that were created fizzled out without troubling Neto in the visitors’ goal.

Domestically, Celtic are good enough that they can patiently move the ball around and wait for the opposition to slip up, then take full advantage. In Europe, however, Rodgers cannot rely on their opponents being so accommodating. Under the Northern Irishman, Celtic continually toil against a well-organised defence and run out of ideas very quickly. Merely knocking the ball from side to side, waiting for an opportunity to present itself simply isn’t going to work against a team of Valencia’s calibre.

READ MORE: Rodgers: Celtic can still progress to Europa League last-16

Ultimately, individual errors at the back cost Celtic the game on Thursday night but the truth of the matter is that Rodgers’ side failed to make any sort of an impression at the other end of the pitch and as a result, never looked like winning. Barring an early pot-shot from Callum McGregor from the edge of the area, Celtic failed to effectively test the Valencia keeper and struggled to fashion opportunities for themselves. Rodgers’ dogmatic approach tactically let Celtic down once again in Europe and until he learns to be more flexible, history is destined to repeat itself.