It was narrated from Ibn Umar concerning the Messenger of Allah ﷺ he said: "He used to set up a short spear then pray facing toward it." (Using translation from Nasāʾī 747)
عَنِ النَّبِيِّ ﷺ «أَنَّهُ كَانَ يَرْكُزُ الْحَرْبَةَ ثُمَّ يُصَلِّي إِلَيْهَا»