production - Was the episode "The Co-Pilot" in Season 2 supposed to be the pilot?

In "The Shield" there is an episode in Season 2 that does not fit into the timeline of the other episodes: Episode 2x09 "The Co-Pilot".

It plays during the time of the opening of the Barn, so even before the first season and introduces the main characters.

There is no explanation why this flashback is occurring and it does not really seem to fit in there. There is nothing revealed that advances the plot of Season 2 somehow.

The name of the episode, the way it looks older than the other ones in the season and the somewhat forced discontinuity made me think that this might have been a pilot that maybe was disapproved.

• What is the story behind this episode?


• Was it filmed prior to season 1? Was it supposed to be the original pilot? If so, why did it not get aired?


• If it was indeed a cancelled pilot, why did it get aired in season 2?