Freeney, 33, had 12 tackles and five sacks last year as the veteran struggled to adapt to the Colts' 3-4 defensive scheme. The Chargers employ the same style defense.
The veteran did, however, tally 34 quarterback hurries, which would've bested Ingram's 29 for the most on the Chargers last season.
San Diego may have an advantage in signing Freeney given that GM Tom Telesco, who joined the team in January, spent the previous 15 years working in the Colts' personnel department.
ESPN's Ed Werder also reported that Chargers coach Mike McCoy would adjust San Diego's defense to better accommodate Freeney, who has 107.5 career sacks.
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