This is just idle speculation with no knowledge behind it, but if Darras was unable to pitch, then it would explain quite a bit right there at least to me on why Darras did not come in and why Penders stayed with Over in the 9th. As for Holmes coming in when he did, I would say at this point that Penders has more confidence in Holmes to do the job than Nepiarsky, who has yet to pitch in a close game, or Montgomerie, who has really only really pitched well in a starting role. For better or worse, Penders just isn't going to go with an untested relief pitcher in those circumstances. I recall that Holmes did have a taste of success in late inning relief work earlier in the season, so I suspect that is why he got the call.