VIDEO: Lackey investigated for potential use of foreign substance

John Lackey was dominant Friday night against the Chicago Cubs, but there may be an asterisk surrounding his start.

The St. Louis Cardinals right-hander oddly touched his left forearm in the seventh inning before rubbing the baseball, prompting the Cubs to ask home-plate umpire Phil Cuzzi to check the ball for signs of a foreign substance.

Cuzzi didn't have any concerns after investigating, and it's possible Lackey has rosin on his forearm, which is permitted to improve grip.

Cubs manager Joe Maddon downplayed the incident after the game, stating he had only asked for the ball to be replaced because it had been in the dirt.

Lackey tossed 7 1/3 scoreless innings in the National League Division Series opener before handing the ball over to the Cardinals bullpen.