Sayyiduna Khawwat bin Jubayr (may Allah be pleased with him) relates: I was praying when someone behind me said: Keep the prayer short, for we have a need of you. I turned around, and it was the Prophet (peace and blessings be upon him).
Al-Tabarani recorded it in al-Mu'jam al-Kabir; its chain contains Abdullah bin Zayd bin Aslam, whom Yahya bin Ma'in and others declared weak, while Abu Hatim and Ma'n bin Isa declared him thiqah (trustworthy). Abu Dawud says: He is like his brother.
Hadith Referenceمجمع الزوائد ومنبع الفوائد / كتاب الصلاة / 2434