Woo (forearm) played catch Monday, Shannon Drayer of Seattle Sports 710 AM reports.
Woo is less than a week removed from landing on the injured list, and he has already been given the green light to throw, which backs up last week's report that the Mariners aren't overly concerned about his forearm injury. He may throw a bullpen session soon, and barring any setbacks, could rejoin Seattle's rotation as early as next week.