Betts is safe.
His injury problems are worth the gamble for this year at least. Next year is a different story if he can't stay healthy this year.
My prediction is that Simon and McCullough are the odd men out.
McCullough is too similar to Portis in style and size, and let's face it, he's only played against backups. If the staff was seriously considering him don't you think we would see him a bit earlier in the game? Last night after Betts left the game Rock came in. That's a sign to me that Rock will make the team.