U.S. trucking firm Yellow Corp filed for Chapter 11 bankruptcy protection on Sunday, burdened with a heavy debt load after a series of mergers and following tense contract negotiations with the Teamsters Union.

(Reporting by Dietrich Knauth in New York, Priyamvada C in Bengaluru, Siddharth Cavale in New York and Lisa Baertlein in Los Angeles; Editing by Sriraj Kalluvila and Dhanya Ann Thoppil)