"I heard Jabir bin 'Abdullah say: 'The Messenger of Allah ﷺ said: "If any one of you comes and the Imam has appeared, let him pray two Rak'ahs. Shu'bah (one of the narrators) said: "On Friday."  

أَنَّ رَسُولَ اللَّهِ ﷺ قَالَ إِذَا جَاءَ أَحَدُكُمْ وَقَدْ خَرَجَ الإِمَامُ فَلْيُصَلِّ رَكْعَتَيْنِ قَالَ شُعْبَةُ يَوْمَ الْجُمُعَةِ