Romero, according to ESPN.com, had the option of opting out of his recent deal with the Nationals if not promoted to the big leagues by July 15. Now, after giving up just one earned run in seven innings for Triple-A Syracuse, Romero is in Toledo, Ohio, with Triple-A Scranton/Wilkes-Barre.
With Damaso Marte and Pedro Feliciano on the shelf for a prolonged stretch, the Yankees' only lefty in the bullpen is Boone Logan.
"It's just an option that we have," Yankees manager Joe Girardi said about Romero. "It's a guy who's pitched in tough markets, it's a guy who's pitched in a big market in pressure situations. So let's just see what he does."
Romero was designated for assignment by the Phillies on June 16, after posting a 3.86 ERA in 16 1/3 innings and limiting lefty hitters to a .208 batting average.
With the Phils from 2008-10, the 35-year-old appeared in an average of 54 games per year, posting a 3.04 ERA, 1.460 WHIP and 1.15 strikeout-to-walk ratio.
Alden Gonzalez is a reporter for MLB.com. Read his columns and his blog, listen to his podcast and follow him on Twitter. This story was not subject to the approval of Major League Baseball or its clubs.