The procedure was reportedly performed by the Jets team doctors and Darnold is not expected to miss any time this offseason.
Costello notes that Darnold dealt with the thumb injury for the final two months of the season after originally suffered the injury while scrambling during their game against the Jaguars. He was forced to wear a brace on his non-throwing hand for the rest of the season.
Darnold, 22, was taken with the No. 3 overall pick in the 2018 NFL Draft by the Jets. He agreed to a four-year, $30,370,490 contract with the Jets that includes a $20,167,628 signing bonus.
The contract will also include a fifth-year option for the Jets to pick up in 2021.
In 2019, Darnold appeared in 13 games for the Jets and completed 61.9 percent of his passes for 3,024 yards, 19 touchdowns and 13 interceptions. He also rushed for 62 yards and two touchdowns.