Marvel is still focusing on “Captain America: The Winter Soldier,” which arrives in April, but sources tell Variety that Anthony and Joe Russo will be back in the director’s chair for a third installment, even though the film hasn’t officially been greenlit.

Marvel and Russo’s reps had no comment.

Negotiations wouldn’t begin untill after “Winter Soldier” bows but sources say Marvel has been so impressed with the production of the film, as well as with strong results from recent test screenings, that the studio has moved fast to attach the brothers to the next installment.

Since many of the actors have options for a third installment, a threequel is likely in the cards as long as “Winter Soldier” performs well.

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A writer and release date are still pending for “ Captain America 3 ” but sources say Marvel and the Russos are already putting together an outline of what the third film’s story arc would look like.

Kevin Feige will produce with Chris Evans returning in the title role.

Going back to “Iron Man,” when Feige announced the first phase of Marvel’s release plans, Feige and the studio have been reluctant to commit to directors for subsequent installments too early in the process.

The Russos, who previously directed over 30 episodes of NBC’s “Community,” stepped in to direct “Captain America: Winter Soldier” in 2012 after Joe Johnson helmed the first installment.

Marvel prefers to get these deals done early so that the director can help develop future sequels. But the studio can also move faster when necessary — when Kenneth Branagh passed on the “Thor” sequel, Marvel landed Alan Taylor.

The move is clearly a vote of confidence for the helmers of “Captain America: the Winter Soldier,” which bows on April 4.

Anthony and Joe Russo are repped by WME.