Tony La Russa admitted he didn't fully know the extra-inning rule that would have allowed him to avoid using closer Liam Hendriks as a baserunner in a 0-0 game against the Reds on Wednesday in Cincinnati.

Hendriks had double-switched into the game in the bottom of the ninth inning, taking the No. 5 spot in the batting order, which made the last out in the top of the frame. Per Major League rules, as extra innings begin, the spot in the order to make the last out in the previous inning becomes the baserunner at second base.

However, if that spot is occupied by a pitcher, the team has the option to use the preceding player in the batting order as the runner. In this case, it would have been Jose Abreu.

"I didn't know that," the Chicago White Sox manager said. "We all thought Liam was going to be the runner. I wasn't aware Abreu could have run. I thought it was the guy that made the last out or the spot in that order."