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
Publius Scato with the Marsians confronted them; he had pitched his camp at the spot where Marius crossed the brook, but, before the passage took place, he had withdrawn thence, leaving behind the mere posts that guarded the camp, and had taken a position in ambush farther up the river. There he attacked the other Roman corps under Lupus unexpectedly during the crossing, and partly cut it down, partly drove it into the river (11th June 664). The consul in person and 8000 of his troops fell. It could scarcely be called a compensation that Marius, becoming at length aware of Scato's departure, had crossed the river and not without loss to the enemy occupied their camp.
Yet this passage of the river, and a victory at the same time obtained over the Paelignians by the general Servius Sulpicius, compelled the Marsians to draw their line of defence somewhat back, and Marius, who by decree of the senate succeeded Lupus as commander-in-chief, at least prevented the enemy from gaining further successes. But, when Quintus Caepio was soon afterwards associated in the command with equal powers, not so much on account of a conflict which he had successfully sustained, as because he had recommended himself to the equites then leading the politics of Rome by his vehement opposition to Drusus, he allowed himself to be lured into an ambush by Silo on the pretext that the latter wished to betray to him his army, and was cut to pieces with a great part of his force by the Marsians and Vestinians.
Marius, after Caepio's fall once more sole commander-in-chief, through his tenacious resistance prevented his antagonist from profiting by the advantages which he had gained, and gradually penetrated far into the Marsian territory. He long refused battle; when he at length gave it, he vanquished his impetuous opponent, who left on the battle-- field among other dead Herius Asinius the chieftain of the Marrucini. In a second engagement the army of Marius and the corps of Sulla which belonged to the army of the south co-operated to inflict on the Marsians a still more considerable defeat, which cost them 6000 men; but the glory of this day remained with the younger officer, for, while Marius had given and gained the battle, Sulla had intercepted the retreat of the fugitives and destroyed them.
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Reference address : https://www.ellopos.net/elpenor/rome/4-07-sulpician-revolution.asp?pg=32