At last regarding Drona to be incapable of being checked by any one else, Yudhishthira placed that unbearable heavy burden on the son of Subhadra.
अशक्यं तु तमन्येन द्रोणं मत्वा युधिष्ठिरः। अविषहां गुरुं भारं सौभद्रं समवासृजत्॥