There were worrying signs for Cincinnati Bengals fans at Thursday's training camp as star quarterback Joe Burrow went down clutching his leg without being tackled.
Burrow, the number one overall pick in the 2020 draft, had to be carted off the field with what is believed to be a calf strain.
The 26-year-old has not had the best of luck with injuries in his career, three months into his rookie season he tore the ACL in his left knee while he also missed the 2022 preseason after undergoing an appendectomy.
Burrow, who is the next quarterback expected to earn a record salary after Justin Herbert's new contract, was already wearing a sleeve on the calf he has injured after feeling soreness earlier in the day.
In 2022 Burrow threw for 4,475 yards and 35 touchdowns in what was another impressive season for the LSU product.
With the 2023 season fast approaching, Bengals fans will have a nervy wait to see if Burrow will be fit to lead the team to what would be his second Super Bowl appearance in three years.
Who are the back-up quarterbacks if Burrow is out?
If Burrow is forced to miss a number of games, the next quarterback up for the Bengals would be Trevor Siemian.
Siemian, 31, was a seventh round pick by the Denver Broncos in the 2015 NFL Draft, though he did go on to become the team's starter.
In 2016, Siemian threw for 3,401 yards and 18 touchdowns with a pass completion rate of just under 60% across 14 games.
The following season he started 11 games, but his high interception rate saw his time with the Broncos come to an end, and since that point he has featured sporadically for the New York Jets, New Orleans Saints and Chicago Bears.
The Bengals' only other current option is Jake Browning, who has spent his career to date on the practice squads of the Minnesota Vikings and since September 2021 the Cincinnati Bengals.
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