The Under-18 Premier League South season ended in defeat for title-winning Chelsea away at Arsenal – but the focus for the young Blues is firmly on Tuesday night's national final at Stamford Bridge.

With the title wrapped in midweek – and our Under-21s needing reinforcements for a Premier League 2 playoff quarter-final clash with Arsenal – Hassan Sulaiman named a starting XI that included several players from our Under-16s.

Arsenal broke the deadlock at London Colney when Chido Martin Obi won and then netted a penalty but the Blues battled back and went into the interval level after Shim Mheuka capitalised on a mistake and struck.

The young Blues went ahead early into the second period when Frankie Runham fired home at the back post, but Arsenal levelled through Max Dowman before Daniel Oyetunde then put the hosts ahead. Martin Obi netted twice more to add gloss to the scoreline.

It wasn't the way Chelsea wanted to end the regular season. Yet the opportunity to be crowned national champions remains when Manchester United visit Stamford Bridge on Tuesday.

Get your tickets as Chelsea Under-18s bid to be crowned national champions!

Necessary changes

The Chelsea side looked very different to that which started our at Southampton. There was an Under-18s debut for Harry McGlinchey, a second appearance for Sol Gordon, third starts for Olutayo Subuloye and Landon Emenalo, and a fourth for Rio Ngumoha.

The Arsenal starting XI – coached by former England international Jack Wilshere – also featured players from younger age groups, and the Gunners started well and carried a threat in the early stages through Martin Obi.

Twice the forward, who came into the game having struck 29 goals, was presented with opportunities to fire toward the Chelsea goal. On both occasions, the 16-year-old was unable to hit the target.

Martin Obi wasn't to be denied, however. On the quarter-hour mark, he attempted to beat Subuloye in the Chelsea box only to go down under pressure. A penalty was awarded and Martin Obi coolly converted beyond Luke Campbell.

Arsenal went in search of a second and Campbell was forced into a smart stop to deny Theo Julienne's effort from distance. The Chelsea goalkeeper then had to collect a shot from Martin Obi that was blocked on its way to goal.

The young Blues hadn't been able to fashion a clear sight of the host's goal in the opening 30 minutes. Fortunately, we were gifted one and Mheuka took full advantage.

As Arsenal attempted to build possession, Mheuka intercepted a square pass inside the Chelsea half. He shifted the ball out of his feet, advanced into Gunners territory, spotted goalkeeper Owen Asemota off his line, and guided a fine finish home from 35 yards.

That goal – coupled with a late save from Campbell to deny Louie Copley – ensured the game was level at the interval.

A change was needed before the restart as schoolboy goalkeeper Jack Austin replaced Campbell. It was just the 16-year-old's third appearance at this level and he was worked early into the second half as a low shot from Andre Annous required saving.

Austin then played a part in the goal that put us ahead in the 56th minute. From inside his penalty area, the young stopper clipped a fine pass out wide McGlinchey, who exchanged passes with Emenalo and burst forward.

The debutant full-back, who was impressive throughout, played the ball across the Arsenal box and Runham crashed the back post to fire beyond Asemota.

Our lead would last just nine minutes – and it was one we would not reclaim. Arsenal levelled when the ball broke kindly into the path of Martin Obi, who played a pass into the path of 14-year-old Dowman. He burst into the Chelsea penalty box to score.

Changes were made by Sulaiman, perhaps with one eye on Tuesday's national final. Goalscorers Runham and Mheuka came off; Shaun Wade and Yahya Idrissi were introduced.

As the contest entered its final ten minutes, the score remained level. Yet it was from that point Arsenal were able to open up their advantage.

The Gunners took the lead when Oyetunde closed down Austin and diverted the Chelsea goalkeeper's attempted pass into the net. Martin Obi then grabbed his second of the game as he headed home a corner from Michal Rosiak.

Almost 15 minutes of stoppage time was played in which Idrissi forced Asemota into a good stop from close range. But more noteworthy was the 101st-minute penalty conceded by captain Akomeah that saw him dismissed after being shown a second yellow card.

Martin Obi stepped up and fired home from 12 yards to complete his hat-trick and inflict the young Blues' first away defeat of their league campaign.

What comes next

Chelsea will compete to become national champions on Tuesday evening as they welcome Manchester United to Stamford Bridge. Your support will be needed and you can buy your tickets here.

The teams

Arsenal: Asemota; Ibrahim (Shuaid 58), Rosiak, Sweet, Samail (Casey 87); Julienne, Copley, Dudziak, Dowman (Kuczynski 87), Annous (Oyetunde 65), Martin Obi
Unused substitutes:
Goalscorers: Martin Obi 16, 85, 90+12, Dowman 65, Oyetunde 81
Booked: Dowman 69, Shuaid 77

Chelsea (4-2-3-1): Campbell (Austin HT); Boniface, Akomeah, Subuloye, McGlinchey (Rodda 86); Gordon, Emenalo, Runham (Wade 70), Cardoso, Ngumoha; Mheuka (Idrissi 70)
Goalscorers: Mhueka 34, Runham 56
Booked: Akomeah 90+7
Sent off: Akomeah 90+11