Fleck (right) was in Rangers' starting line-up against Arbroath
Rangers forward John Fleck has joined Blackpool on loan until the end of the season, a move that leaves Sheffield United disappointed for a second time.
The 20-year-old Scotland Under-21 international travelled south to meet managers of both English clubs earlier this week.
But he chose Ian Holloway's Championship promotion hopefuls.
United's Danny Wilson was also thwarted in his attempt to sign Fleck at the end of the summer transfer window.
The League One outfit reached an agreement to take the nephew of former Scotland striker Robert Fleck and Rangers team-mate Kyle Hutton.
But the deal for the two Under-21 internationals failed to beat the deadline and midfielder Hutton subsequently joined Partick Thistle on loan until December.
It had looked like Fleck would join Blackpool earlier this month, but an injury to Rangers striker Kyle Lafferty put the Scot's departure from Ibrox in doubt.
Fleck came off the bench to replace the Northern Ireland international in a 3-0 win over Motherwell and started the 4-0 victory over Arbroath in the Scottish Cup.
However, he was back as an unused substitute for Saturday's 2-1 win over St Johnstone, whose own striker, Francisco Sandaza, has become a target for the Glasgow club.
Rangers were willing to allow Fleck to leave in the search of regular first-team football despite continued speculation about the future at Ibrox of Nikica Jelavic.
The Croatia striker has himself attracted interest from English clubs, including West Brom, although Rangers say there have been no cash bids and manager Ally McCoist stresses that he would not welcome any.
Both the Blades, who presently lie second behind Charlton Athletic in League One, and the Seasiders agreed terms with Rangers to take Fleck until the end of the season.
But he has chosen Blackpool, who sit ninth, three points adrift of sixth-top Hull City, as they chase a promotion play-off place in the league above.
He will hope to emulate Charlie Adam, who left for Blackpool after falling out of favour at Ibrox but eventually won a big-money move to Liverpool and elevation to Scotland's full international side.
Fleck joins former Rangers captain Barry Ferguson and Danny Wilson, the former Ibrox defender now on loan from Liverpool, in the Blackpool squad.
Meanwhile, failure to sign Fleck could result in United boss Wilson resurrecting his interest in Hutton.