A very public decision by Russia to order the withdrawal of its forces from the southern Ukrainian city of Kherson appears to be a necessary humiliation.
Exposed on the west bank of the Dnipro River, commanders faced the choice of staying and slowly dying under Ukrainian bombardment or retreating and living to fight another day.
Ukrainian troops will rightly be wary of a trap, designed to draw them forward into Russian fire.
But if - as it seems - President Vladimir Putin's forces are genuinely retreating to new defensive lines on the opposite side of the river, it will mark an important win for Ukraine as well as a much-needed psychological boost after more than two-and-a-half months of a bloody counter-offensive in the south.
The big question now is whether the Ukrainians can exploit their momentum to keep pushing the Russians back, or will the frontlines literally and metaphorically freeze until the spring?
Both sides are exhausted, have suffered heavy casualties and face increasingly difficult fighting conditions as winter closes in, seeing temperatures drop and visibility worsen.
But there is little doubt that Ukraine's armed forces will want to continue to fight, provided their western partners continue to deliver weapons and ammunition.
It is the single biggest factor on the Ukrainian side that the government in Kyiv cannot control, beyond keeping up the pressure on their US, British and other NATO suppliers.
For Mr Putin, though, he will doubtless be hoping - as has happened all too often in the past - that the ability of the West to stay the course will falter when things become too tough and drag on beyond too many election cycles.
He will be counting on soaring energy prices, tanking economies and increasingly unhappy populations in western nations piling pressure on their respective governments to change course on Ukraine.
Despite his troops underperforming and failing in the north, east and now the south, the Russian leader is showing no sign of backing down or altering his plans to seize Ukraine.
He just needs time to regroup, rearm and wait for the bulk of some 300,000 reservists recently mobilised to gain a semblance of training so they can attempt new offensives.
That means the West's will and ability to stick with Ukraine needs to outlast Mr Putin's will to wage war.