Millwall and Real Sociedad played out an exciting 3-3 draw in The Lions' final pre-season friendly at The Den on Saturday afternoon.
Shaun Williams missed an early penalty for the home side, but after The Lions were gifted a second spot-kick on 20 minutes, Jed Wallace made no mistake to open the scoring.
Strikes from Alexander Isak and David Zururuza turned the game on its head, but Ben Thompson levelled with a fantastic strike shortly into the second-half. Sociedad had other ideas, though, and nudged themselves into the lead again through Isak, before Connor Mahoney curled a stunning effort home late on to secure a draw.
Neil Harris opted to field a strong XI against the La Liga outfit, with Aiden O'Brien partnering Den debutant Matt Smith in attack, whilst both Frank Fielding and Mahoney also played their first game in SE16.
The Lions started brightly and nearly fashioned a chance with four minutes on the clock, but after Jed Wallace's ball found Williams, the midfielder's through ball could not be controlled by O'Brien.
Just seconds later, Smith was brought down inside the box and a penalty was awarded, but Williams' take kick was easily stopped by Alejandro Remiro.
With 20 minutes on the clock, The Lions received another spot-kick as Jake Cooper was hauled down in the box from a corner - Jed Wallace stepped up and struck the ball hard, and despite Remiro getting a hand to to it, it had enough to creep over the line and open the scoring.
Just two minutes later, however, a defence-splitting ball allowed Sociedad to equalise, as Isak slotted past a helpless Fielding.
In an eventful game, Mahoney's free-kick evaded everyone at the midway point of the first-half but could only hit the post, before captain Alex Pearce's follow-up was stopped by the face of Joseba Zaldua.
On 31 minutes, Sociedad nudged themselves into the lead as Zururuza was allowed time and space to pick his spot and sweetly strike past Fielding.
Shortly before the half-time break, Mahoney's deep free-kick was headed back across goal by Pearce, but no Millwall man was there to tap home the equaliser.
The second-half began in the same way that the first did, with chances galore at either end - and Thompson's thunderbolt from the edge of the area levelled the scores on 49 minutes.
Sociedad, however, had other ideas, and nosed themselves in front once more in the 53rd minute as Isak tapped home from close range.
A host of substitutions from the visitors shortly after the hour-mark freshened things up for the Spaniards, but it was Millwall who had the next chance on 66 minutes, however Cooper headed Mahoney's corner-kick over the crossbar.
It was Millwall's turn to make use of subs with 19 minutes remaining, with Sociedad having the next attempt as substitute Andoni Gorosabel forced Fielding into a save. Artiz Elustondo then glanced wide as the visitors looked to extend their lead.
Eight minutes from time, a five-goal thriller became six as a cross-field pass was touched into the path of Mahoney by Mahlon Romeo - the winger then beat his man with style before curling a superb effort beyond Remiro and into the far corner of the net.
The action wasn't over there, however, with Elustondo planting a free header over the crossbar, before the Sociedad man blazed over on the final whistle.
Millwall: Fielding, M. Wallace (Ferguson 71'), Cooper, Williams (Leonard 71'), J. Wallace (Skalak 71'), Thompson (Mitchell 87'), Smith (Bradshaw 71'), Romeo, Pearce (Hutchinson 71'), Mahoney, O'Brien (Bodvarsson 71'). Sub not used: Sandford.
Scorer: J. Wallace pen 20', Thompson 49', Mahoney 82'
Real Sociedad: Remiro, Zaldua, Illarramendi, Sagnan, Januzaj, Munoz, Zururuza, Isak, Odegaard, Le Normans, Djouahra. Subs: Rulli, Llorente, Portugues, Da Silva, Pardo, Elustondo, Gorosabel, Rodrigues, Navas, Guevara Lajo, Lopez, Zubiaurre, Zubimendi.
Scorer: Isak 22' 53', Zururuza 31'
Referee: Tim Robinson