Musannaf Ibn Abi Shaybah 6027 — One who has missed a rakah and whom

Ibrahim was asked about a person whom the imam appointed as his deputy after one rak'ah had passed, while he himself had missed that rak'ah: what should he do? He said: He should lead the people in the rest of the prayer; when he has completed the prayer, he should take hold of a man who prayed that rak'ah and put him forward; when that man gives the salam, he should stand up and complete his own prayer.