The deal is for three years and $39 million, sources told ESPN's Adam Schefter, and includes $26.5 million in guarantees and more than $20 million fully guaranteed.
The Giants also signed wide receiver Kenny Golladay to a four-year, $72 million deal over the weekend.
Jackson, 25, was recently released by the Titans. He was in high demand, with the Philadelphia Eagles in the mix until the final moments, according to a source. Jackson was scheduled to visit the Eagles after the Giants on Monday.
New York now adds Jackson to a defense that already had Pro Bowl cornerback James Bradberry on one side. The hope is that the speedy Jackson is the ideal complement to the longer, more physical Bradberry.
Jackson also brings versatility with the ability to play in the slot and serve as a returner.
The Titans drafted Jackson 18th overall in the 2017 draft. Tennessee had picked up his fifth-year option last year but released him last Tuesday, a day before his $10.244 million salary for the 2021 season was set to become fully guaranteed with the beginning of the new league year.
He started 41 of 46 games with Tennessee but a knee injury just before the start of last season limited him to three games in 2020.
Giants make another free-agent splash by signing Adoree' Jackson
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