'Arrow': What's Next for SPOILER After "Brothers In Arms"?

Tonight's Arrow saw its titular character deal with a new problem -- and the fallout could be pretty major.

Spoilers for tonight's episode of Arrow, "Brothers In Arms", below!

The episode saw Oliver Queen (Stephen Amell) realizing that he wanted to hold on to the Green Arrow mantle, a piece of news that he knew he had to break to John Diggle (David Ramsey).

Diggle didn't take the idea very well, and began to get upset at Oliver. Ultimately, Diggle realized that he was angry because of the way that Oliver was approaching being the Green Arrow. As he put it, Oliver was being the Green Arrow partially for himself, instead of completely for the sake of saving the city.

Diggle and Oliver began to physically fight over it, before making up and teaming up in the field. When they returned to the Arrow Cave, Diggle decided that he couldn't accept Oliver's leadership style, and decided to leave Team Arrow.

Diggle then told Lyla about his decision, and how he wished he could still help the city in some capacity. Lyla then offered that Diggle help her run ARGUS, a position that he accepted.

Considering the role that Diggle has played in Arrow's events -- literally being by Oliver's side almost since the series started -- this twist might be surprising for some. And while there's no telling if Diggle leaving Team Arrow will last, and if his fate as the Emerald Archer might not be completely sealed, this definitely could effect the show's landscape for the time being.

And judging by recent comments from Arrow EP Marc Guggenheim, it sounds like Diggle's choice will have an impact on Oliver as a part of the larger storyline of this batch of episodes.

"This season has been very much about removing all of the support structures from Oliver," Guggenheim explained during a recent interview. "One of the challenges we placed for ourselves in season 6 was we got Oliver to the end of his emotional journey in Season Five. He finally moved on from the past, he was a much more emotionally complete human being."

"So the challenge for Season Six was: How — in a show that really, for the first five years, gained a lot of its story from the bad choices Oliver made — do we continue to make Oliver's life difficult, but have it come from something that he's enduring rather than the dark machinations of the soul?" Guggenheim explained. "One of the things we hit upon is the idea of we spent basically season 5 building up this team and this whole support structure, bringing him closer to Felicity again, bringing his son into his life. And in season 6 what you've basically seen, and will continue to see, is the slow degradation of all those structures."

What do you think of this Arrow bombshell? Sound off in the comments below.

Arrow airs Thursdays at 9/8c on The CW.