To the north of Pretoria a second force was acting under Grobler, while a third under De la Rey had been despatched secretly across to the left wing of the British, north-west of Pretoria.

While Botha engaged the attention of Lord Roberts by energetic demonstrations on his right, Grobler and De la Rey were to make a sudden attack upon his centre and his left, each point being twelve or fifteen miles from the other.

It was well devised and very well carried out; but the inherent defect of it was that, when subdivided in this way, the Boer force was no longer strong enough to gain more than a mere success of outposts.
De la Rey's attack was delivered at break of day on July 11th at Uitval's Nek, a post some eighteen miles west of the capital.

This position could not be said to be part of Lord Roberts's line, but rather to be a link to connect his army with Rustenburg.

It was weakly held by three companies of the Lincolns with two others in support, one squadron of the Scots Greys, and two guns of O battery R.H.A.The attack came with the first grey light of dawn, and for many hours the small garrison bore up against a deadly fire, waiting for the help which never came.
All day they held their assailants at bay, and it was not until evening that their ammunition ran short and they were forced to surrender.
Nothing could have been better than the behaviour of the men, both infantry, cavalry, and gunners, but their position was a hopeless one.
The casualties amounted to eighty killed and wounded.