Former Blue Jay Eric Thames was the one who broke the story with a Tweet from the plane with his former Las Vegas 51s teammate Moises Sierra.
I had guessed that the Moises Sierra would be the one called up to fill one of the outfield spots after Travis Snider's trade. It was less that I have brilliant foresight and more that there really is not a whole lot of options left in Las Vegas at this point.
Sierra, 23, played in exactly 100 games with Las Vegas this season, and in 422 plate appearances recorded a slash line of .289/.360/.472, homering 17 times to go along with 16 doubles. He was Bluebird Banter's #25 ranked prospect this year.
There has been no announcement yet about possible corresponding roster moves. The Blue Jays will need to remove two players more from their 25-man roster with the additions of Sierra, Brad Lincoln, and Steve Delabar.
UPDATE: Shi Davidi reports that Joel Carreno and Evan Crawford will be optioned to free the needed roster spots.