Whats with the bullpen confusion?

As the fans wait another day for the 2011 World Series to resume, it leaves another day to try to figure out what happened in the 8th inning of the Rangers' 4-2 win over the Cardinals. It was unbelieveably similar to what happened to the Mets and pitcher Tim Byrdak during a game this past season. Byrdak was given what he thought was a call to come in to the game and started jogging in. He had to stop and start jogging back to the bullpen because he was not supposed to be in the game.
Of course we know that Cardinals manager Tony La Russa is known for making pitching changes and sometimes makes too many. What we hear now is that he wanted to use closer Jason Motte. Apparently La Russa wanted to use Motte to face Mike Napoli, who ended up coming up with the winning hit. Motte was not up and ready when LaRussa came to take Mark Rzepczynski out of the game. So Rzepczynski remained in the game and gave up the winning hit. The funniest thing happened next when LaRussa came to get his pitcher and it was Lance Lynn, and not Motte, who came in from the bullpen. LaRussa later said that Lynn was not available to pitch and didn't know why he was in the game. Lynn would intentionally walk Ian Kinsler before he was taking out of the game. So thats why Lynn was brought in to the game just to walk a batter and come out of the game. Maybe LaRussa was shocked when he realized the wrong pitcher was coming in, but why couldn't he had sent him back? In my interpretation, the pitcher is not in the game until he reaches the infield dirt. If I'm wrong, somebody please clarify the rule. Maybe Tony was gassed from jogging to the mound too much and couldn't muster up enough energy to run out and stop Lynn. Maybe it just wasn't important since they gave up the lead. A lead that was given up because Tony LaRussa didn't have the pitcher he wanted in the game.