Please note that Mommsen uses the AUC chronology (Ab Urbe Condita), i.e. from the founding of the City of Rome. You can use this reference table to have the B.C. dates
From: The History of Rome, by Theodor Mommsen
Translated with the sanction of the author by William Purdie Dickson
Sulla Proceeds to Latium to Oppose the Younger Marius - His Victory at Sacriportus - Democratic Massacres in Rome
The army of the Optimates was divided. The proconsul Metellus undertook, resting on the support of the Picenian insurrection, to advance to Upper Italy, while Sulla marched from Campania straight against the capital. Carbo threw himself in the way of the former; Marius would encounter the main army of the enemy in Latium. Advancing along the Via Latina, Sulla fell in with the enemy not far from Signia; they retired before him as far as the so-called "Port of Sacer," between Signia and the chief stronghold of the Marians, the strong Praeneste. There Marius drew up his force for battle.
His army was about 40,000 strong, and he was in savage fury and personal bravery the true son of his father; but his troops were not the well trained bands with which the latter had fought his battles, and still less might this inexperienced young man bear comparison with the old master of war. His troops soon gave way; the defection of a division even during the battle accelerated the defeat. More than the half of the Marians were dead or prisoners; the remnant, unable either to keep the field or to gain the other bank of the Tiber, was compelled to seek protection in the neighbouring fortresses; the capital, which they had neglected to provision, was irrecoverably lost.
Do you see any typos or other mistakes? Please let us know and correct them
Reference address : https://www.ellopos.net/elpenor/rome/4-09-cinna-sulla.asp?pg=40