David McGoldrick has signed a new deal, committing himself to the Blades until the summer of 2021.
The forward, who arrived on a free transfer after a successful trial with United, following his release by Ipswich Town last summer, has featured in all 28 league games for Chris Wilder's side this term.
McGoldrick has scored 10 goals in 23 starts, forming an excellent partnership with skipper Billy Sharp.
Speaking after seeing the 31-year-old put pen-to-paper on the new contract, boss Chris Wilder commented: "David came in on a short-term deal but has been outstanding for us in the first-half of the season and we are confident he will continue producing.
"His goals have been vital, but his general contribution, including excellent link-up play, has been fantastic. He has made a vital contribution to the club, on and off the field, and we are delighted to reward him."