Cam Skattebo -- the New York Giants breakout rookie running back who has electrified their offense -- was carted off the field after a big hit seemingly left his ankle facing the wrong way.

The 23-year-old fourth-round pick out of Arizona State University took the field against the Philadelphia Eagles ... and, as he was running over the middle on a passing route, when a ball came his way -- and an Eagles defender dragged him down from behind.

Check out the clip ... the Philly player puts all his weight down on CS -- and his legs get caught underneath him as he hits the turf awkwardly.

Almost immediately, Cam's teammates are waving over the medical staff ... and it's easy to see why at the end of the video -- Skattebo's ankle is seemingly twisted the wrong way.

Giants and Eagles players came together at midfield to show love for the injured rookie ... who was then taken away via cart. There's no official word yet on the injury -- but it looks to be season-ending.

Skattebo and fellow Giants rookie Jaxson Dart have pumped life into the New York Giants this season, turning them into the talk of the NFL ... though it seems Dart may be on his own for the foreseeable future.