Thrown back by the rapid Ukrainian offensive in the Kharkiv region east of Ukraine, the Russians were going to have to dig in somewhere.
And now we can begin to see where.
They are certainly making a stand at Svatove, east of the Oskil River.
This is really important to them because Svatove controls the last good supply route from Belgorod in Russia to their forces further south.
But the Ukrainians are now in a position to attack the P66 highway that runs south from Svatove towards Kremenna, on the northern doorstep of the Donbas.
So the Russians are also trying hard to regain their positions at Kremenna, because if they cannot, then Lysychansk and Severodonetsk – remember them? – could be surrounded from the north.
So the next phase of this battle in the northeast is taking shape.
In the southwest, the battle for Kherson continues.
Kherson is the more important strategic objective and Russian troops are fighting hard to retain it.
It appears that the Ukrainians are working to squeeze Russian forces elsewhere in the region back into the city itself. And then probably wearing them down.
Russia’s response to these setbacks has been to launch more rocket attacks against civilian targets and infrastructure.
The dam and hydroelectric plants at Kryvyi Rih were attacked repeatedly. There is military logic in this for Russia.
Breaking the dam floods the Inhulets River and that destroys some of the pontoon bridges the Ukrainians depend on now they have crossed the Inhulets.
The dam is rapidly repaired, the pontoon bridges are replaced, and Russian attacks on the dam will probably continue.
It is all part of the battle of logistics – without which frontline battles will always fail.
And when it comes to logistics and support, some of the headline figures are pretty dramatic.
The Russians have lost more than 6,000 pieces of significant equipment – the Ukrainians only about a quarter of that.
But these big Russian losses are still generally small in terms of the amount of equipment available. Whereas Ukrainian losses are a bigger proportion of what they can ultimately throw into the battle.
This emphasises two fundamental issues.
One is that Ukraine will need Western military equipment for as long as it fights this war.
And two, that means we are witnessing the return of industrial-scale warfare to Europe – for the first time in a couple of generations.