Piet Cronjé believed that Roberts would attempt to attack him in a flanking manoeuvre from the west, and that the advance would largely continue as before along the railway line. With this mind, Roberts ordered Methuen to advance with the 1st Division on 11 February in a feint movement on Magersfontein, while General Sir Hector MacDonald led the Highland Brigade west to Koedoesberg, thereby encouraging Cronjé's forces to believe that the attack would occur there. However, the bulk of the force initially headed south to Graspan, then east deep into the Orange Free State with the cavalry division guarding the British right flank by securing drifts across the Riet River. On 13 February, Roberts activated the second part of his plan, that involved French's cavalry separating from the slower main force and piercing forward quickly by swinging northwards, just east of Jacobsdal, to cross the Modder River at Klip Drift.