Today, in the top of the 9th, one of Brett or Dave mused that Berkman was available on the bench to PH, and was wondering when to use him. The same person then started listing the hitters due up for the Astros. Bourn, Keppinger, Tejada, Lee, etc. After getting through that list, the same announcer commented "I'm not sure I see a good spot to pinch hit Lance until you get through Blum's spot in the lineup."
Also, in case you were wondering, the radio guys objection to pinch hitting Berkman for Keppinger was not based on all the defensive shifting that would have been necessary if they had scored a run or more.