The Red Bulls acquired midfielder-forward Saer Sene and an international roster slot from the New England Revolution in exchange for striker Andre Akpan and allocation money.
"Saer, who can play wide or up front, will add a different dimension and another option to our attack," said Red Bulls sporting director Andy Roxburgh in a news release. "We're excited to bring him aboard and, at the same time, we wish Andre all the best with his new club."
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Sene, 27, has compiled 17 goals and eight assists over three seasons with New England. But the Frenchman, who has come back in recent years from major ankle and knee injuries, has scored just one goal in 10 games (five starts) this season.
Akpan, 26, has notched four goals in five MLS seasons with the Colorado Rapids and New York. He has played just 16 minutes in 2014.
New York (6-7-10) is fourth in the Eastern Conference, two points ahead of seventh-place New England (8-12-2).