Core, who re-signed with the team this offseason, suffered the non-contact injury during Tuesday's practice and was carted off the field.
It's a blow to the Giants, especially their special teams, an area where new coach Joe Judge is expected to put a heavy emphasis. Core was the team's best gunner last season and led the Giants with six special-teams tackles, which earned him a two-year, $4 million deal this offseason.
His absence opens the door on special teams and at wide receiver. Recently claimed wideout C.J. Board is among the candidates who could fill the void. Veteran Corey Coleman, Alex Bachman and undrafted rookies Austin Mack, Binjimen Victor and Derrick Dillon are some other potential replacements.
Originally a sixth-round draft choice out of Ole Miss by the Cincinnati Bengals in 2016, Core was claimed by the Giants off waivers last September. His speed became an immediate asset as a gunner on the punt team. He recorded five of the top 10 speeds among all Giants players in 2019, including the fastest time at 21.93 mph, per Next Gen Stats.
Core caught three passes for 28 yards last season. He has 33 career catches for 388 yards and one touchdown in 51 games with the Giants and Bengals.