The Messenger of Allah ﷺ used to pray Dhuhr at the height of the midday heat, and no prayer was harder on the companions of the Prophet ﷺ than this one. Then the verse was revealed, "Guard strictly the prayers, and the middle prayer" [Baqarah 2:238]. He said, "There are two prayers before it and two prayers after it."
حدثنا محمد بن جعفر حدثنا شعبة حدثني عمرو بن أبي حكيم قال سمعت الزبرقان يحدث عن عروة بن الزبير
كان رسول الله ﷺ يصلي الظهر بالهاجرة ولم يكن يصلي صلاة أشد على أصحاب النبي ﷺ منها قال فنزلت {حافظوا على الصلوات والصلاة الوسطى} وقال إن قبلها صلاتين وبعدها صلاتين
Its chain of transmission is sahih. Amr bin Abu Hakeem is Wasiti, and Zubarqan is Ibn Amr bin Umaya, both being trustworthy and virtuous, and their hadith appears in the Sunan. This hadith was narrated by Abu Dawud, 1/112, no. 411, in the book of Prayer, on the time of Asr prayer.