The 6-foot-6, 240-pound LaCosse was signed by the Giants as an undrafted free agent on May 7 and waived Aug. 1. He adds depth to what has become a crowded tight ends spot, joining Jeff Cumberland, Jace Amaro, Kellen Davis, Steve Maneri, Wes Saxton and Arthur Lynch. Amaro has a sprained shoulder and will not play against the Giants on Saturday night.
LaCosse had 38 catches for 397 yards and six touchdowns in four seasons for Illinois.
Walls, signed in May as an undrafted free agent out of Syracuse, hurt a calf during the team's practice at Hofstra University on Sunday night.
AP NFL websites: http://www.pro32.ap.org and http://www.twitter.com/AP-NFL