The Giants (1-1) will have a short week to prepare for a Sunday 1 p.m. game against the Tennessee Titans (0-2) at MetLife Stadium.
Meanwhile, Dart wasn’t the only Giants player who flew home with an injury.
Outside linebacker Brian Burns suffered a low ankle sprain, and left tackle Andrew Thomas (groin) did not finish the game. Additionally, Malik Nabers injured his shoulder, but the wide receiver was able to return in the first half.
In last week’s 28-20 win over the Cowboys, Dart became the first quarterback in NFL history to open a season with at least three passing touchdowns, 50 rushing yards, and a passer rating of 130.
On Monday, he completed three of five passes for 20 yards before suffering the injury on the seventh play from scrimmage.
Veteran backup Jameis Winston played the rest of the way, completing 11 of 27 passes for 111 yards and an interception while being sacked twice. Overall, the Rams recorded eight quarterback hits and 10 passes defensed.
The Giants have a third quarterback, third-year pro Jake Haener, on the practice squad.
“[We have] absolute faith in all of our players,” Harbaugh said. “That’s why all the guys are here, and Jameis is one of our guys who obviously is here for a reason. He’s a very good football player, but that would go for any position, any player on our team. They would be the next person. Injuries in the National Football League are part of it. That’s at any position. [Cornerback] Tae [Banks] was out this last game. It was tough. You’ve got to find a way to overcome those kinds of things and play through it because guys come back and it’s a long season.”