The Messenger of Allah ﷺ was seen with traces of mud on his forehead and on the tip of his nose from a prayer he had led the people in.
حدثنا ابن المثنى حدثنا صفوان بن عيسى حدثنا معمر عن يحيى بن أبي كثير عن أبي سلمة
أن رسول الله ﷺ رئي على جبهته وعلى أرنبته أثر طين من صلاة صلاها بالناس
Bukhari narrated it in the Book of adhan, Chapter on prostrating with the nose in the mud during sujud, hadith no. 813, and Muslim narrated it in the Book of fasting, Chapter on the merit of Laylat al-Qadr and the encouragement to seek it, etc., hadith no. 1167, from the hadith of Yahya bin Abu Kathir, with this chain.