It's a green light for these Green Lantern co-stars!

Rumored couple Ryan Reynolds and Blake Lively were spotted leaving his Boston apartment early Saturday morning with their dogs in tow. See more pics of Blake and Ryan in Boston.

Their budding romance has been milling since Lively, 24, parted ways with her beau of five months Leonardo DiCaprio earlier this month. (Reynolds officially divorced Scarlett Johansson in July.) The Gossip Girl actress has been spotted visiting Reynolds for three weekends in a row now in Boston, where the 33-year-old is currently shooting action flick R.I.P.D.

In addition to a sushi date, the pair was also spotted at Beantown's South Station, where Reynolds was seen giving Lively an affectionate goodbye.

"They're seeing each other casually," a Lively source tells Us Weekly of the duo. "Now they're both single and trying it out."