It is narrated from Nafi' that Sayyiduna Abdullah bin Umar (may Allah be pleased with them both) fell unconscious and lost his senses, and he did not make up the prayer.
And Imam Malik (may Allah have mercy on him) said: That is because the time had passed; as for whoever recovers while he is within the time, he will pray.
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الصلاة / 1818