Messenger of Allah ﷺ used to pray two brief rak'ahs between the adhan and the Iqamah of Subh prayer. (Using translation from Nasāʾī 1769)
أَنَّ رَسُولَ اللهِ ﷺ كَانَ يُصَلِّي رَكْعَتَيْنِ خَفِيفَتَيْنِ بَيْنَ النِّدَاءِ وَالْإِقَامَةِ مِنْ صَلَاةِ الصُّبْحِ