Whoever does not find a place for prostration (with the Imam) because of overcrowding
حَدَّثَنَا صَدَقَةُ، قَالَ أَخْبَرَنَا يَحْيَى، عَنْ عُبَيْدِ اللَّهِ، عَنْ نَافِعٍ، عَنِ ابْنِ عُمَرَ ـ رضى الله عنهما ـ قَالَ كَانَ النَّبِيُّ صلى الله عليه وسلم يَقْرَأُ السُّورَةَ الَّتِي فِيهَا السَّجْدَةُ فَيَسْجُدُ وَنَسْجُدُ حَتَّى مَا يَجِدُ أَحَدُنَا مَكَانًا لِمَوْضِعِ جَبْهَتِهِ.
Narrated Ibn `Umar.: Whenever the Prophet (ﷺ) recited the Sura which contained the prostration of recitation he used to prostrate and then, we, too, would prostrate and some of us did not find a place for prostration.