Boston College quarterback Thomas Castellanos, who lost his starting job earlier this week, will not be returning to the team, he announced Thursday night.

Castellanos, who started 12 games last season and retained the top job under new coach Bill O’Brien, wrote on X that “unfortunately, all good things come to an end, even though it’s sooner than I would like.” He did not mention the transfer portal in his departing message and has not officially entered it. The junior from Waycross, Georgia, started his career at UCF and appeared in five games in 2022.

O’Brien said Tuesday that Grayson James, who replaced Castellanos in last week’s win against Syracuse, will start Saturday when Boston College visits No. 14 SMU. Castellanos “wasn’t real thrilled” with the decision, O’Brien said, adding that the quarterback decided to step away from the team for several days.

Castellanos had 2,248 passing yards and 1,113 rushing yards last season under coach Jeff Hafley, passing for 15 touchdowns and adding 13 on the ground. He had 18 touchdown passes and only five interceptions this season, but his accuracy dipped in recent weeks, and he completed only 2 of 7 passes against Syracuse before being replaced.

In his statement, Castellanos thanked both coaching staffs he played for at Boston College and wrote that he had “some of the best experiences of my life in the Eagles Nest and I will truly cherish these memories forever.”