The Miami Dolphins shuffled the deck at the tight end position days before the start of the regular season.
While the Dolphins did not disclose Gray's injury, NFL Network Insider Ian Rapoport reported Gray suffered a torn Achilles during Wednesday's practice, via a source informed of the situation.
With Gray officially on the sidelines, backups A.J. Derby and rookie Mike Gesicki are in line for more action.
The player to keep an eye on, however, is Gesicki, whom the Dolphins selected in the second round as the 42nd overall player in the 2018 NFL Draft. The 6-foot-6, 245-pound Gesicki did his part to turn heads with his athleticism and ability to be a target in the red zone during training camp.
Here are other injuries we are monitoring:
1. Atlanta Falcons safety Keanu Neal left in the third quarter after suffering a knee injury in Thursday's season-opening loss to the Philadelphia Eagles. He was ruled out by the team a short time later and did not return. However, coach Dan Quinn said after the game that it, "doesn't appear to be anything serious." Running back Devonta Freeman left the game in the fourth quarter after suffering a knee injury.
2. Jacksonville Jaguars tight end Austin Seferian-Jenkins (core muscle injury) was limited at practice.
Another situation to monitor for the Jaguars: Cornerback Jalen Ramsey was limited Thursday due to ankle soreness. Any issue for Ramsey could be big in his matchup Sunday against Odell Beckham.
3. The Indianapolis Colts' offense received good news as running back Marlon Mack returned to practice for the first time since he injured his hamstring during an Aug. 9 preseason game against the Seahawks.
4. Kansas City Chiefs safety Eric Berry remains sidelined with his preseason heel injury, missing a second consecutive practice. It looks increasingly unlikely that Berry, who tore his Achilles tendon in the 2017 season opener, won't be ready to go Sunday.
5. Cleveland Browns cornerback E.J. Gaines (knee) likely won't play Sunday despite participating in individual drills Thursday, according to head coach Hue Jackson.
6. The Minnesota Vikings' health is improving as Week 1 approaches. Cornerback Mackensie Alexander (ankle) returned to practice, per NFL Network's Tom Pelissero. Center Pat Elfein (ankle/shoulder) also was in uniform for the start of practice.
7. The Philadelphia Eagles placed wide receiver Mack Hollins (groin) on injured reserve.
8. Houston Texans wide receiver Sammie Coates was limited in practice because of a hamstring injury. Linebacker Whitney Mercilus (hamstring) and wide receiver Will Fuller (hamstring) also were limited.
9. New England Patriots first-round pick Sony Michel was limited with a knee injury. Defensive back Duke Dawson sat out practice with a hamstring injury.
10. Tampa Bay Buccaneers rookie defensive tackle Vita Vea (calf) did not practice.
11. Cornerback Mackensie Alexander (ankle) returned to practice and was limited after sitting out Wednesday. Offensive tackle Aviante Collins was limited with an elbow injury and cornerback Marcus Sherels was a full participant coming off an ankle injury.
12. New York Jets safety Marcus Maye (foot) and wide receiver Jermaine Kearse (abdomen) did not practice on Thursday.
13. Los Angeles Chargers defensive end Joey Bosa (foot) didn't practice on Thursday, one day after participating in a limited fashion. Bolts coach Anthony Lynn told reporters that it's possible Bosa does not play in L.A.'s opener against the Chiefs.
14. Oakland Raiders running back Marshawn Lynch was limited in practice with a groin injury. Linebacker Tahir Whitehead (ankle) and offensive lineman Kelechi Osemele (back) also were limited.
15. Los Angeles Rams linebacker Mark Barron did not practice because of an ankle injury.