The cruelty of football is that Sam Gallagher’s lasting memory of this amazing game might be his miss from six yards – but it really shouldn’t be.

The 18-year-old, handed the daunting task of making his first ever senior start, produced a performance to be proud of and more than played his part in a thrilling night.

Had he planted his shot just inside, rather than outside, of the post in the 36th minute it would have been the perfect evening for him.

But that missed opportunity should not detract from a display that marked him out as another serious prospect for the future.

Mauricio Pochettino had said before this contest that he would have “no fear at all” in starting the teenager in a big Premier League game.

On this evidence, you could see why.

Going up against the Premier League leaders, who also boasted the top-flight’s best defence coming into this match, not much could realistically have been expected of Gallagher, who only got his first senior goal on Saturday, in the 2-0 FA Cup win against Yeovil, and was deputising here for the injured Rickie Lambert.

But he was one of many thorns in Arsenal’s side, particularly during an outstanding first half from the home team.

Gallagher twice went close to scoring in the opening ten minutes, first deflecting Luke Shaw’s cross just wide of the near post and then stinging the hands of Wojciech Szczesny with a powerful right-foot shot.

The former Plymouth player, who moved to Saints two years ago at the age of 16, was working tirelessly, closing down when Saints didn’t have the ball, and attempting to run beyond the Arsenal defence when they did.

You sensed a big opportunity would at some point come his way, and it did when Nacho Monreal’s clearance from inside his own area hit Steven Davis and spun across the six-yard box.

Gallagher, perhaps slightly off balance, could not convert, sending his right-foot effort wide. As he picked himself up off the turf, he looked somewhat crestfallen.

But he showed no ill-effects, and was in the thick of things again a few minutes later, latching onto the ball at the end of a sensational little move in the Arsenal area that started with him and involved an Adam Lallana backheel and a 360-degree spin from Steven Davis.

His sweetly-struck shot looked destined to fly past Szczesny, but Laurent Koscielny’s outstanding sliding block denied him.

By the time he was withdrawn after 70 minutes, Gallagher had done more than enough to earn a standing ovation from the Saints fans.

He might not have got his dream goal, but if he keeps playing like this then there will no doubt be plenty to come in the future.