The 3rd Brigade moved back towards the fighting in the afternoon of Tuesday, 19th September 1916 to support the divisions in the frontline. 2 WELCH took up positions along the north eastern edge of Mametz Wood, 1 GLOUC in Bazentin le Grand Wood, 2 R MUN FUS in Mill Street and Chester Street and 1 SWB was just north of Bazentin Le Grand.
2 companies of 1 SWB were employed that night digging up Cork Alley and two companies of the 2 R MUN FUS were employed carrying loads for 140th (4th London) Brigade of the 47th (2nd London) Division who lost Drop Alley before being relieved by the 1st Brigade.
On Wednesday, 20th September 1916 1/6th WELCH arrived during the morning and had to be fitted in with the battalions of the Brigade in Mametz Wood. Brigadier-General Davies visited the units in the wood during the day. 1 GLOUC moved from Bazentin le Grand Wood back to Mametz Wood in relief to 1 NORTH'N who moved back to Black Wood. 1 SWB and two companies of 1 GLOUC were employed in the night opening up a communication trench (Cork Alley) running up to the Switch Line from Worcester Trench to the east of High Wood. 2 R MUN FUS were called forward to act as carrying parties for the 1st Brigade.
Thursday, 21st September 1916 was a fine day and in the afternoon a company of 1 GLOUC continued the work on Cork Alley with the remaining three companies carrying on the work throughout the night. In the afternoon it was arranged that two battalions of the 3rd Brigade would be placed temporarily at the disposal of the 1st Brigade and 2 WELCH and 2 R MUN FUS were the battalions selected. These two battalions moved up to the 1st brigade that evening and 2 WELCH replaced the 1st Battalion, the Royal Highlanders (Black Watch) [1 BLACK WATCH] in the right front of the 1st Brigade and 2 R MUN FUS took over the Flers First and Support lines and Goose Alley from a battalion of the 2nd New Zealand Brigade.
Friday, 22nd September 1916 was also a fine day. At 13.00 to 15.30 hrs the 3rd Brigade's headquarters were heavily shelled and at intervals thereafter. 460 men of 1 SWB were employed throughout the day carrying forward loads to 2 WELCH and 2 R MUN FUS and 200 men of 1 GLOUC were employed to bring back 50 wounded men belonging to the 47th Brigade of the 16th (Irish) Division from Cough Drop. Two companies of 1 GLOUC continued working on Cork Alley.
Saturday, 23rd September 1916 was another fine day. Brigadier-General Davies assumed command of the frontline at 09.00 hrs and he visited 2 WELCH and 2 R MUN FUS in the line. During the day work was continued by 1 GLOUC to deepen Cork Alley, 1 SWB worked on a trench joining Flag Lane and the communication trench running north into Flers Trench, 2 WELCH worked on repairing and strengthening their positions in the frontline and communication trenches back from their positions to Drop Alley assisted by 1/6th WELCH, and 2 R MUN FUS improved their trenches in general and the T head in Goose Alley.
During the evening of the 23rd 1 SWB replaced the 8th Battalion, the Royal Berkshire Regiment [8 R BERKS] in the line and at 22.00 hrs the Germans made a bombing raid on the forward post close to the junction of Flers Support and Goose Alley. This attack was repulsed and patrols sent out during the night reported that the enemy was holding the front and support trenches of the Flers Line about 30 yards to the north of this post in strength. An attack had been planned to take place that night by 2 R MUN FUS, but owing to the enemy's activity this was postponed.
On Sunday, 24th September 1916 Brigadier-General Davies visited 2 WELCH and 2 R MUN FUS in the frontline. At 20.30 hrs A Company, 2 R MUN FUS attacked the German held Flers Line from positions in Goose Alley. At the same time two bombing parties moved forward along the Flers frontline and Flers Support trenches with C Company 2 R MUN FUS moving a bound behind. Three minutes after leaving their assembly trenches A Company, 2 R MUN FUS had taken their objective. Within 15 minutes they had sustained around 25 casualties and were being hard pressed.
Progress by the bombers in Flers Support was slow due to enemy machine gun fire and enemy bombing and only five men of the party made it to the first German barricade. The bombing party in Flers Trench got on better than that in Flers Support. This meant that C Company 2 R MUN FUS who were following behind them had advanced about 30 yards in Flers Support, closest to A Company, and about 80 yards in Flers Trench by 20.45 hrs. This forced the withdrawal of the enemy machine gun that they were trying to take, but resulted in five other enemy machine guns being brought into action against them.
C Company and D Company quickly got to work putting barricades in an effort to hold on to the gains made as A Company and the bombers were slowly forced backwards. Half of D Company was ordered to reinforce A Company, but they came under severe machine gun fire and was unable to reach A Company. A fierce contested developed between the three companies of 2 MUN FUS and the enemy and they were slowly forced back to the original positions by 22.00 hrs.
Throughout this fighting A Company 1 SWB was employed carrying supplies between 2 R MUN FUS dump in the rear to the dump in Goose Alley and half of B Company 1 SWB was employed carrying supplies to the front.
The attack ultimately failed due to the severity of the German counterattack, the enemy's strength and their formidable use of their machine guns.
During the early morning of Monday, 25th September 1916 1 BLACK WATCH minus two companies relieved 2 R MUN FUS and two companies of 1 SWB in the Flers Line and their CO, Lieutenant Colonel Victor Morven Fortune DSO, took over the command of this sector. In addition to his own men, Lieutenant Colonel Fortune had two companies of 2 R MUN FUS and one company of 1 SWB under command. They deployed with one company of 1 BLACK WATCH forward, one company of 2 R MUN FUS behind them and the company of 1 SWB behind them again in Flers Trench and one company 1 BLACK WATCH forward with the remaining company of 2 R MUN FUS behind them in Flers Support.
At 06.00 hrs the enemy made a determined bombing attack against the forward posts in the Flers Trench, Flers Support and Goose Alley saps. They succeeded in driving 1 BLACK WATCH group out, but Lieutenant Colonel Fortune's composite force counterattacked and drove the enemy back and reoccupied the posts. The enemy left seven dead in the trench.
At 12.35 hrs on Monday 25th September 1916 XIV Corps attacked behind a creeping barrage. This attack marked the beginning of the Battle of Morval and 1 BLACK WATCH group attacked the enemy in the Flers Line in cooperation with this assault. The two companies of 1 BLACK WATCH supported by the two companies of 2 R MUN FUS and one company of 1 SWB pushed forward up Flers Trench and Flers Support. There was not much resistance in Flers Trench but Flers Support was strongly held. Barricades were thrown up about 200 yards up both trenches and the enemy repeatedly bombed the one in Flers Support. This effectively prevented any further progress and the barricades were consolidated. The Germans sustained casualties of 40 or so killed and ten wounded and unwounded prisoners were taken. 1 BLACK WATCH group's casualties amounted to 4 officers and 112 other ranks.
That night the 3rd Brigade was relieved by the 2nd Brigade and went into reserve. The 3rd Brigade's headquarters, 1 SWB and the Machine Gun Battalion moved back to Albert; 1 GLOUC, 2 R MUN FUS and the Trench Mortars moved into positions near Black Wood; and 2 WELCH moved to Becourt Wood. On Thursday, 28th September 1916 the 3rd Brigade moved back further into the rear at Millencourt and the following day they returned to the Henencourt Wood.
The 1st Division was subsequently pulled away from the fighting and did not return towards the front until 17th November 1916 by which time the fighting had died down and the Battle of the Somme had drawn to a close.