Dallas Cowboys quarterback Tony Romo broke his left collarbone in Sunday's 20-10 win over Philadelphia, spoiling his team's 2-0 start.
Romo said tests on Monday will likely determine how long he's out.
It's likely the Cowboys will have to play without Romo and wide receiver Dez Bryant for a while. Bryant is expected to be out for at least a month with a broken right foot.
Romo was sacked and slammed onto the turf late in the third quarter against the Eagles. X-rays on the shoulder revealed the broken collarbone. He clutched his left shoulder and was down for several minutes before he sat up and eventually walked off the field. Romo returned with his left arm in a sling. He had a similar injury in Week 7 in 2010 and missed the rest of the season.
Earlier in the day, Buffalo Bills safety Aaron Williams went through a series of tests on his neck and head area and was released from a hospital. Williams was hurt after diving to make a tackle in a 40-32 loss to New England, landing his helmet on receiver Julian Edelman's back and having his head bounce off the turf. Bills coach Rex Ryan said Williams was taken to the hospital for what he called a ''cervical precaution.''
Chicago Bears quarterback Jay Cutler left a 48-23 loss against Arizona with an injury. Cutler was stiff-armed while trying to make a tackle on an interception return and landed on his right shoulder, though the team said he left the game because of a hamstring injury.
San Francisco running back Carlos Hyde was taken out of a 43-18 loss at Pittsburgh because of a head injury, and 49ers coach Jim Tomsula said the rookie was cleared after an evaluation for a concussion. Hyde ran for 43 yards on 14 carries gaining 168 yards and two yards on the ground in Week 1.
In other injury news:
- Detroit Lions quarterback Matthew Stafford had X-rays on his chest and ribs after a 26-16 loss at Minnesota. Stafford was seen shaking his right arm, which was banged up in the opener, in pain at several points through the game.
- Miami Dolphins running back Lamar Miller had an ankle injury in a 23-20 loss to Jacksonville. Miller was limited to 14 yards rushing on 10 carries over the first three quarters of the game.
- New York Giants cornerback Dominique Rodgers-Cromartie sustained a concussion after a second-half injury during a 24-20 loss to Atlanta. Giants left tackle Ereck Flowers went out with a sprained left ankle in the second half. Falcons rookie running back Tevin Coleman hurt his ribs in the first half after scoring his first career touchdown.
- Philadelphia linebacker Kiko Alonso, acquired from Buffalo for LeSean McCoy, left in the first half because of an injured left knee. He missed all of last season with a torn anterior cruciate ligament in the same knee. Eagles linebacker Mychal Kendricks was also injured against the Cowboys, leaving the game with an injured hamstring.
- Houston right tackle Jeff Adams was carted off the field in the second quarter after trainers put an air cast on the right leg. Adams was engaged with Carolina defensive end Kony Ealy when his leg gave out and he fell to the ground. Teammates immediately yelled for the trainers and took a knee around him during the 24-17 loss at Carolina.
- Tennessee offensive guard Chance Warmack strained a knee ligament in a 28-14 loss at Cleveland and is scheduled for an MRI on Monday.
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