Musannaf Ibn Abi Shaybah

Hazrat Abu Saeed, Hazrat Ibn Umar (may Allah be pleased with them), and Hazrat Ibn Zubair, regarding the person who begins prayer with the Imam but misses a part of the prayer, state that he should do as the Imam does. When the Imam completes his prayer, he should perform the missed part of his prayer and perform two prostrations of forgetfulness (sujood as-sahw).

Hazrat Jabir bin Zaid says that if you miss the Tashahhud after two rak‘ahs, then do not sit to recite Tashahhud in your own rak‘ah, rather follow the Imam.

Hazrat Zuhri, regarding the person who joined the congregation from the beginning but missed one rak‘ah, states that he should continue to follow the imam, and when the imam finishes the prayer, he should stand up and make up the missed rak‘ah.

Hazrat Uqbah bin Abi Aizar says that I asked Ibrahim about a person who joins the prayer with the Imam, but misses one rak'ah, and if the Imam makes a mistake (sahw), then what should he do? He replied that when he has joined the prayer with the Imam, he should do whatever the Imam does.