Southend have signed Millwall striker Neil Harris, subject to a medical.
United boss Paul Sturrock has made Harris his first signing of the summer by securing the 33-year-old on a three-year deal.
The Lions agreed to allow their all-time record goalscorer to leave the Den, despite him having one year remaining on his contract.
Harris has made over 500 career appearances and scored a phenomenal 176 goals in a career that has spanned 14 years and included two spells at Millwall.
Lions boss Kenny Jackett said: "Neil is a legend at Millwall and has been a fantastic servant to this club.
"His goalscoring record at this football club is not likely to be beaten in a hurry and I have a feeling that this will be a case of au revoir and not goodbye as far as Neil and Millwall are concerned."
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