Midfielder Martyn Woolford has joined Sheffield United on a two-year contract.
Woolford, 29, spent the last two seasons at Millwall and scored 11 goals in 79 appearances.
He worked with manager Nigel Adkins at Scunthorpe United, scoring at Wembley to secure the club's 2009 promotion to League One.
Adkins told the club website: "Martyn is fit, strong, robust and honest and has a fantastic professional attitude."
He continued: "We are very aware of the talents Martyn brings to Bramall Lane.
"He has been consistently available for selection over many seasons and knows the demands required of this level."
Woolford is Adkins' first summer signing since he was appointed as United's manager in June.
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