On the day of Al-Khandaq (the trench), `Umar bin Al-Khattab went to the Prophet (ﷺ) and said, "O Allah's Messenger (ﷺ)! By Allah, I could not pray (the `Asr) till the sun had set." `Umar told this to the Prophet at the time when a fasting person had done Iftar (taken his meals). The Prophet (ﷺ) then went to Buthan and I was with him. He performed ablution and offered the `Asr prayer after the sun had set and then the Maghrib prayer.