स यदि यजुष्टो रिष्येद्भुवः स्वाहेति दक्षिणाग्नौ जुहुयाद्यजुषामेव तद्रसेन यजुषां वीर्येण यजुषां यज्ञस्य विरिष्टँ संदधाति ॥ ५ ॥
In plain words
If the sacrifice suffers a flaw on the side of the Yajus formulas, one should offer an oblation in the Southern fire saying, 'Bhuvaḥ, svāhā!' Through the very essence and potency of the Yajus, he heals the broken parts of the sacrifice.
Close to the Sanskrit
If that sacrifice should suffer a flaw from the Yajus side, one should offer an oblation in the Southern fire with 'Bhuvaḥ svāhā!'. By the essence alone of the Yajus, by the potency of the Yajus, he heals the broken part of the sacrifice related to the Yajus.