The people of Kufa complained about Saad to Umar, saying that he did not pray properly.Saad said, "These Bedouins! By Allah, I never failed to pray with them according to the prayer of the Messenger of Allah ﷺ. In the noon and afternoon prayers, I would lengthen the first two units and shorten the last two."I then heard Umar say, "That is what we expected of you, Abu Ishaq."
حدثنا سفيان عن عبد الملك سمعه من
شكا أهل الكوفة سعدا إلى عمر فقالوا إنه لا يحسن يصلي قال آلأعاريب والله ما آلو بهم عن صلاة رسول الله ﷺ في الظهر والعصر أركد في الأوليين وأحذف في الأخريين فسمعت عمر يقول كذلك الظن بك يا أبا إسحاق
Its isnad is sahih, and it is a repeat of 1518. Sufyan here is Ibn Uyayna, while Sufyan there is Thawri. Ahmad narrates the hadith with a higher chain from Ibn Uyayna from Abdul-Malik bin Umayr, and he also narrates it with a lower chain from Abdul-Razzaq from Thawri from Abdul-Malik bin Umayr.