Collins' statement comes after Benjamin Allbright of Mile High Sports Radio reported Giants players "hate" McAdoo and "no one trusts him."
Per ESPN's Josina Anderson (via James Kratch of NJ Advanced Media), one unnamed Giants player said McAdoo has "lost the team."
"He's going 80 percent on Saturdays (in practice) before we get on a plane, it's wild," the player told Anderson. "Changed our off day. He's dishing out fines like crazy. Suspended two of our stars when we need them most. Throws us under the bus all the time. He's ran us into the ground and people wonder why we've been getting got."
The Giants hired McAdoo in January 2016 after he spent the previous two seasons as their offensive coordinator. He had a successful debut season, leading the team to an 11-5 record and a playoff appearance where they lost to the Green Bay Packers, 38-13, in the NFC Wild Card round.
New York will travel to Levi's Stadium in Week 10 for a game against the winless San Francisco 49ers on Sunday.