The door back to the NFL has officially been shut for Colin Kaepernick

Early in the NFL offseason, Colin Kaepernick had a lot of momentum.

As free agency got underway after the Super Bowl, unique storylines developed

Since quite some time, the former San Francisco 49ers quarterback has been training for a comeback

His possible comeback gained momentum when he worked out with Seattle Seahawks receiver Tyler Lockett

According to the Las Vegas Raiders, he also worked out with them.

In spite of the fact that he wasn't looking for a starting role, Las Vegas decided not to use him as a backup for Derek Carr

Training camps begin in just a few weeks, so a return to the NFL for the upcoming season seems unlikely

In the early part of this offseason, Kaepernick had several options for securing a job and a starting role