A trade involving the Cardinal’s Levi Brown and the Steelers has been made official today according to the Cardinal’s official twitter feed:
— Arizona Cardinals (@AZCardinals) October 2, 2013 
Brown must pass a physical on Thursday before the trade becomes official.
The trade for Brown likely signals the end of the Mike Adams experiment at left tackle for Pittsburg. Adams, a second-round pick in 2012, moved from right to left tackle in the offseason and has struggled to protect quarterback Ben Roethlisberger’s blind side.
There are questions about how much of an upgrade Brown, who is signed until 2016 with a $4.75 million base salary this season, would be over Adams.
Source: Adam Schefter and Scott Brown ESPN NFL Cardinals Trade Brown To Steelers For Conditional Draft Pick by Sports Talk Florida