Matty Sparrow has left the club after turning down a contract extension.
Sparrow, 28, had spent 10 years as a professional at Glanford Park after coming through the youth system.
"We are disappointed but appreciate his decision and wish him well in the future," the Iron chairman, Steve Wharton, told the club's official website.
"He has been an excellent player for our club and played an important part in many of our recent successess."
Sparrow played 396 times for the Iron, scoring 41 goals. His most high-profile strikes were the two which helped United defeat Millwall 3-2 in the 2009 League One play-off final.
Sparrow, 28, had spent 10 years as a professional at Glanford Park after coming through the youth system.
"We are disappointed but appreciate his decision and wish him well in the future," the Iron chairman, Steve Wharton, told the club's official website.
"He has been an excellent player for our club and played an important part in many of our recent successess."
Sparrow played 396 times for the Iron, scoring 41 goals. His most high-profile strikes were the two which helped United defeat Millwall 3-2 in the 2009 League One play-off final.