[2] The initial plan of the Central Powers' offensive was for a two-pronged assault: the Austro-Hungarian 1st Army would attack in the Tatros-Ojtoz (Trotuș-Oituz) area with the aim of occupying the pass and interrupting lines of communication across the Siret valley to prevent the arrival of Russian aid, while the German 9th Army had as its objective "the opening of the road over the mountains to Bucharest, on the shortest way, so that the entire western territory of Muntenia would be cut as with a knife".

The 3rd German Cavalry Division commanded by General Eberhard von Schmettow was stationed centrally in Brassó (Brașov), able to be deployed immediately to exploit the success, in case the Romanian front was broken, either in the gorge of the Jiu or in the Oituz.

Romanian general Constantin Prezan called on troops in the North Army to counter-attack on the 11th and push back the opposition from the border, although it is not clear whether this was in response to the advance by the XXI Austro-Hungarian Corps, which begun on the 8th.

[12] In any case, on the 11th, the Romanians attacked in three columns over an extended area, with the aim of pinning the forces present and prevent the transfer of reinforcements elsewhere along the front by causing heavy losses to their opponents.

The attacks continued on the 12th, with the Bavarians having to push back eight successive assaults on the recently captured border heights, which were carried out impetuously, to the sound of music.

An order from the Chief of the Austrian General Staff, Franz Conrad von Hötzendorf, placed four battalions and five batteries in reserve at Kézdivásárhely to reinforce the defenders of the pass.

The first of these set out eastwards along with a Székler battalion and managed to clear out a border post which had been taken by the Romanians, and then the second was tasked to recapture the summit of the Runcul Mare after some preparation was conducted.

[15] If the danger to Austro-Hungarian positions was thus averted to the east of the Oituz valley, the Gyalu Leszpedin, now held by the 5th (Bosnian) Infantry Regiment, was attacked three times during the day.