We started superbly, asking plenty of questions of the hosts' backline, and broke the deadlock in the 26th minute through yet another Grimwade set piece.

Rabbaj claimed our second with a placed finish into the left corner just after the half-hour mark, but the score was 2-1 at the break as Tyrone Omotoye pulled a goal back for the hosts.

In the second period, we re-established our two-goal lead thanks to Ebho. Unfortunately, West Ham scored three goals in six minutes to make it 4-3 and, while we tried to equalise, the Hammers had the final say as they netted their fifth of the afternoon.

Strong start

The Blues came racing out the blocks, piling pressure on West Ham’s backline. Within seven minutes, we had earned three corners, and our pressure midway through the half was after Rabbaj received the ball on the right flank and made a darting run towards the penalty area.

His quick feet and pace were too much for the West Ham defence, who were forced to foul the Moroccan in a dangerous area. Grimwade stepped up and continued to prove himself as a free-kick specialist, firing the ball into the far corner.

Rabbaj extended our lead five minutes later, netting his first goal of the season. Jayden Malundama came close to marking his return to the starting eleven with a goal but was thwarted by Felix Lewis-Ayesta. The loose ball fell to the edge of the box and Rabbaj picked his spot perfectly.

He almost had a brace before the interval when he spotted the Hammers keeper off his line at the start of another attack. Rabbaj went for the spectacular from the halfway line and wasn’t far away, his effort whistled just wide of the right post.

However, in the final action of the half, West Ham made it 2-1 through Omotoye.

Netting a third

Hungry for more in the second period, Rabbaj kept testing Lewis-Ayesta and troubling the opposition. We had an array of chances, with Andrew Pennie unlucky not to turn his header toward goal and Jashayde Greenwood a whisker away from close range.

It was Ebho who got our third, though, as he collected the ball off Grimwade and let fly from distance. His effort took a deflection and beat Lewis-Ayesta to reinstate our two-goal advantage.

Caught out

It wasn't one we were able to keep, though. With 20 minutes remaining, we were caught in possession and Jude Longman halved the deficit once more.

The Blues responded well initially, as Greenwood's thumping strike was tipped onto the crossbar by Lewis-Ayesta, earning us a corner. Unfortunately, we were caught on the counter and punished as Omotoye got his second of the afternoon and equalise for the Hammers.

Moments after the leveller, we conceded a penalty which Longman converted to put us behind for the first time in the contest. We pushed for an equaliser but West Ham managed a fifth before the final whistle to inflict our first defeat since the start of September.

What it means

This defeat sees us drop to 2nd position and remain on 21 points. We now trail the league leaders by two points.

What comes next?

Chelsea Under-18s host Charlton Athletic in the Premier League Cup on Saturday 7 November at Cobham Training Ground. The game gets underway at 11am GMT and supporters can watch the match live with a CFC+ subscription.

The teams

Chelsea (4-3-3): Toby Bell; Riley Ebho (Gabriel Sambou60’), Dante Waite (Josh Henry 64’) (C), Jacob Hall, Yisa Alao; Isaac Badu, Jayden Malundama (Bilal Shah-Berkouz 79’), Heze Grimwade; Ibrahim Rabbaj, Jashayde Greenwood, Andrew Pennie (Isaac McGillvary 60’)
Unused subs: Isago Silva, Rico Sealey
Scorers: Grimwade 26, Rabbaj 31, Ebho 54
Booked: Malundama 45, Rabbaj 68, McGillvary 70, Badu 89

Manager: Dan Hogan

West Ham (4-3-3): Felix Lewis-Ayesta; Isaac Thoams, Tomas Jonyla (Zak Magowan 83’), Arnaldo Bato Ugate, Reon Smith; Reginald-Ray Agyemang, Tyrone Omotoye, Jude Longman (Oluwadarasimi Akinlolu 87’); Martin Peychev, Chuk Obi, Jephthah Medine
Unused subs: Charles Gadsdon, Jack Tomlin, Mitchell Brown, Lenny Noble, Glenn MacAj
Scorers: Omotoye 45+2 74, Longman 71, 77, Akinlolu 90+4
Booked: Ugate 13, Jonyla 20, Magowan 85, Medine 90+4

Manager: Luke Smith