If Odalis Perez leaves his start Saturday writhing in agony, the trade for Brad Penny is looking pretty savioriffic.

Instead, it's Penny who runs off the mound Sunday like his arm was caught in a grease fire, and life in Dodgertown takes on a whole new meaning, pending the diagnosis.

The twin scenarios illustrate both the rationale and the risk behind the acquisition of Penny. Was Penny an injury risk? Perhaps, but you can't ask that question without asking the same about Perez. Both have had a history of arm troubles - Perez as recently as a month ago. A more proper question would address the relativity of the risk among the pitchers.

Today, the Dodgers have eight starting pitchers on their 25-man roster and disabled list, with immediate questions surrounding half: Penny, Edwin Jackson, Hideo Nomo and Kazuhisa Ishii (who had been demoted less than 24 hours before Penny's injury), not to mention lingering concerns about the long-term health of Perez and the long-term viability of Wilson Alvarez, Jose Lima - and what the hell, Jeff Weaver, too.

While many will find Penny's early departure Sunday adding injury to the insult of the Paul Lo Duca trade, I don't think it requires too convoluted a journey, as bizarre as it sounds, to conclude that Penny's injury justifies his acquisition. The Dodgers have been playing well, but their starting pitching is like strapping tape, nearly impossible to tear - until it is punctured, that is.

Depending on how long we must wait for Penny to recover, the ability for displaced starters Jackson, Nomo and Ishii to pitch effectively, which two days ago was considered gravy, now becomes the meat. And unless you're really willing to place your faith in Giovanni Carrara as a starter, then the acquisition of another starting pitcher, either from the Dodger minor league system or from another team, once more becomes a potential need.

Optimistically, Ishii still has enough brilliance amid his fluctuating performance levels to bridge the cap between now and a Jackson, Nomo or Penny recovery. Dodger manager Jim Tracy was correct in stating Saturday that the Dodgers had five starting pitchers more worthy of pennant race participation than Ishii. However, just because Ishii was No. 6 does not mean he is hopeless.

But the ride isn't done being rocky, is it?

Update: From Will Carroll at Baseball Prospectus:

One of the best indications of the severity of an injury is the player's initial reaction. Dodgers fans were very worried when Brad Penny pulled up in the first inning yesterday, grabbing at his right bicep. After a quick talk with the assistant trainer and pitching coach, Penny threw another pitch, grabbed at his arm again and nearly ran from the field. Some reports have him screaming or groaning. It looked bad, and no, I'm not sure what the trainer was thinking by allowing him to throw.

Paul DePodesta's trades really haven't been going the Dodgers' way so far. The game of baseball has its own interesting ways of making us remember that phrase about the best-laid plans. Steve Finley is dealing with his normal sore hamstrings, so the Dodgers are smartly giving him a chance to rest up as they have a nice cushion in the standings. There's little to be concerned about; in fact, the intelligent usage and rest actually improves his chances of being useful over the last two months of the season and into the playoffs