How I Met Your Mother star Cobie Smulders is the lead contender to play SHIELD Agent Maria Hill in The Avengers, Deadline reports, edging out actresses Morena Baccarin, Jessica Lucas and Mary Elizabeth Winstead.

Speculation about the role began early Thursday when Samuel L. Jackson revealed on Late Night With Jimmy Fallon that he would screen test actresses on Friday to play Nick Fury's "sidekick" in the movie. A report quickly followed indicating that four actresses were vying the role of a key member of SHIELD, making Sharon Carter, Carol Danvers or Maria Hill the likely Marvel character.

The 28-year-old Smulders, who had a recurring role in The L Word, was Avengers director Joss Whedon's choice to star in his abandoned Wonder Woman movie. According to Deadline, her Marvel deal -- it's expected to include the studio's now-standard nine-picture option -- could be finalized before the weekend is out.

Debuting in Marvel comics in 2005, Maria Hill served as interim executive director, and then deputy director, of SHIELD before being appointed by Steve Rogers to lead a new team of Avengers.

The Avengers, which is set to begin filming in April, stars Robert Downey Jr., Chris Evans, Chris Hemsworth, Scarlett Johansson, Mark Ruffalo, Jeremy Renner, Samuel L. Jackson and Clark Gregg. It opens on May 4, 2012.