The Fourth Army advance on 25 September was its deepest since 14 July and left the Germans in severe difficulties, particularly in a salient which developed to the north-east of Combles.

Deteriorating weather and the shorter days greatly increased British and French transport difficulties; rain and fog grounded aircraft and impeded artillery observation.

Despite the small numbers of tanks available and the limited time for the training of crews by September 1916, Haig had committed them in the Battle of Flers–Courcelette, in view of the importance of the general Allied offensive being conducted on the Western Front in France, by Italy against the Austro-Hungarians and by Brusilov in Russia, which could not continue indefinitely.

On the nights of 19 and 20 September, parties of the 56th (1/1st London) Division consolidated a line west and north-east of Combles, from Beef Trench to Middle Copse.

[6] The preliminary bombardment began on 24 September but a thick autumn mist in the morning and hazy conditions all day, reduced the amount of counter-battery fire that could be delivered.

[8] A conference at the British Fourth Army headquarters on 26 September, arranged the move of the inter-army boundary to run from Lesbœufs, north-east towards Rocquigny.

[9] Foch intended to resume the French attack from Mont St Quentin, east of the Somme bend to Combles, at the boundary with the British Fourth Army.

The Sixth Army was to advance 3,000 yd (1.7 mi; 2.7 km), close to the German line running from Moislains to Le Transloy.

[8] In the south, VI and XXXIII corps would advance east and south-east, to establish a defensive flank along the Tortille stream, menacing Péronne from the north.

Distant objectives east of the Péronne–Bapaume road were selected, should the German defence collapse and the cavalry was made ready to prolong an advance.

Spurs ran down the eastern slope, generally to the north-east in the direction of the Péronne–Bapaume road, before the ground rose again from St Pierre Vaast Wood to Sailly-Saillisel, Le Transloy, Beaulencourt and Thilloy.

The first step was an advance to the third of the objective lines set for 15 September and to the Gird Trenches (Gallwitz Riegel) south of Gueudecourt, beginning at 12:35 p.m.

[18] The cessation of German attacks at Verdun, ordered by the new supreme command of Chief of the General Staff, Field Marshal Paul von Hindenburg and the Erster Generalquartiermeister General Erich Ludendorff, when they superseded Falkenhayn and the reinforcement of the Somme front, reduced the German inferiority in guns and aircraft on the Somme during September.

[20] As the Germans had been pushed out of their original defences, Loßberg had new positions dug based on the principles of depth, dispersal and camouflage, rather than continuous lines of trenches.

The area behind the front-line was defended by support and reserve units dispersed on reverse slopes, in undulations and in any cover that could be found, so that they could open machine-gun fire by surprise, from unseen positions and then counter-attack swiftly, before the Anglo-French infantry could consolidate captured ground.

Rather than pack troops into the front-line, the local, corps and army reserves were held back, in lines about 2,000 yd (1,800 m) apart, able to make progressively stronger counter-attacks.

[22] Trenches were still dug but were no longer intended to be fought from, being used for shelter during quiet periods, for the movement of reinforcements and supplies, as rallying points and decoys.

After another halt to reorganise, the village was occupied by the 15th Brigade at 3:00 p.m..[28] The final objective from the Moulin de Morval windmill, south to the 56th (1/1st London) Division area, was consolidated by nightfall.

A German counter-barrage began on the Guards Division front, within a minute of the infantry advancing but the leading waves moved fast enough to avoid the bombardment.

The neighbouring brigade of the 21st Division had been held up by uncut wire, so a defensive flank was formed; the rest of the brigade pressed on, arriving at the second objective at 2:35 p.m. and the final objective at 3:30 p.m. Touch was gained with the 6th Division north of Lesbœufs; a further advance in the evening was postponed due to the vulnerable northern flank, although the disarray seen among the German defenders further south, led local commanders to call for cavalry to exploit the "rout" they believed was occurring south of Gueudecourt, as British artillery inflicted many casualties on retreating parties of Germans.

[34] In XIV Corps the 56th (1/1st London) Division probed towards Combles, arriving within 500 yd (460 m) by dawn, as other troops advanced into Bouleaux Wood, after seeing rockets fired at 2:10 a.m.

[35] Infantry probes beyond Lesbœufs, made little progress against a line of German machine-gun posts, on the higher ground west of Le Transloy.

[39] A XV Corps attack by the New Zealand Division was cancelled, because the un-captured part of Gird Trench was found to overlook the objective at Goose Alley.

[44] Monday 25 September, was bright and cloudless, with a ground haze but reports from observers in contact patrol aircraft were notably accurate, as the infantry advanced to their objectives on the Fourth Army front, from Morval to Gueudecourt and around Flers.

Lagnicourt aerodrome was attacked by two British squadrons, causing damage to hangars and parked aircraft and a German headquarters was bombed at Manancourt.

After 30 minutes the defenders were forced back to within 500 yd (460 m) of the Guards Division, when the aircraft called for artillery fire until the tank and infantry arrived.

Troops of the 8th Division, brought from north of the Bapaume–Albert road, to counter-attack from Thilloy towards Gueudecourt, were engaged by sixty British field guns, causing the German infantry to "flee" in the direction of Le Transloy.

[52] The battle was a considerable Anglo-French victory and as no tanks were used in the initial Fourth Army attack, a continuous creeping barrage was maintained.

Cavalry were even able to seize some tactical objectives and infantry kept well up to the creeping bombardment, limiting losses to 5,000 men in the ten British divisions engaged.

The Anglo-French had made important gains of ground and inflicted many casualties on the German armies but their advance in the Morval area had been contained, leading to more mutually costly fighting in the Battle of Le Transloy (1 October – 5 November) in colder and wetter autumnal weather.