Bradshaw underwent X-rays on his neck after exiting in the second quarter. He will undergo an MRI on Monday, a league source told ESPN NFL Insider Adam Schefter.
New York's leading rusher each of the last two seasons, Bradshaw spent the second half on the sideline in a T-shirt and shorts cheering on his team.
Diehl, one of the most veteran members of the Giants' offensive line, suffered a knee injury in the first quarter on a goal-line play. He has been injured in recent years, but with hamstring and hip issues. Tackle Sean Locklear replaced Diehl.
Hixon also left the game in the first quarter and has been diagnosed with a concussion. It would be very unlikely for a concussed player to be cleared for contact in four days under the new NFL protocols, which require approval both from the team and an independent physician.
Giants coach Tom Coughlin didn't have any concrete updates after the game on any of the players.
"We are in a goal-line situation, and you usually don't think that is a danger situation and we have David Diehl, he's been like an iron man around here and he gets hurt," Coughlin said. "And I didn't even know the circumstance around Bradshaw's injury, but the next thing you know he is out."
Hixon was injured after catching a 12-yard pass. Tampa Bay linebacker Mason Foster was called for a personal foul after making contact with Hixon's head on the play. Hixon got up slowly and appeared a bit shaken up.
Hakeem Nicks appeared to hurt his foot after an incomplete pass later in the contest. He missed one play, but returned to catch a 20-yard pass and added another 50-yard catch in the last scoring series as the Giants took a final lead.
"For him to come out and play like that through a foot that was bothering him fresh off a surgery, I'm just inspired by his play," Victor Cruz said.
Coughlin gave Nicks the game ball.
"The coach was telling me great effort, great game and we'll continue to build on that," Nicks said.