What is "Salat ul-Wusta" mentioned in Surah Al-Baqara? A friend says it is "Fajr" prayer since our Islamic day starts at "Maghrib" (sunset).

Praise be to Allah, the Lord of the Worlds; and may His blessings and peace be upon our Prophet Muhammad and upon all his Family and Companions.

The majority of the scholars are of the view that Salat ul-Wusta (the middle prayer) is Asr prayer.  Their evidence is from the saying of the Prophet (Sallallahu Alaihi wa Sallam) on the day of Al Ahzab: "They kept us busy from the middle prayer (we missed it), Asr prayer, may Allah fill their homes and graves with fire." [Reported by Muslim and others]

However, some scholars argue that it is Zuhr prayer.  This is the preponderant opinion according to the writer of ‘Dibaj in the interpretation of Saheeh Muslim Bin Hajjaj.’

Some other scholars say that it is Fajr prayer.  The Hadith mentioned above is an evidence against everyone.

Allah knows best.