The 18-year-old left-sided centre half has signed a two-and-a-half year deal with Rovers and is targeting a push for the first team as soon as possible.
He said: “The aim is just to get as fit and strong as I can using the facilities here and put in the hard work.
"If I keep working hard I can eventually get into the first-team.
“I’m working with the fitness coaches now, then hopefully I can get a few games for the Development team to show the gaffer and the lads what I can do.”
From Letterkenny in County Donegal. Blaney captained Republic of Ireland Schoolboys last year.
As well as operating at centre half, he can also feature at left back or in midfield.
He made one senior start and two substitute appearances for Finn Harps, who play in the second tier in the Republic of Ireland.
And he thanked staff at the club for helping his progression.
He said: “They played a big role, from going from my hometown clubs to Finn Harps was a big step up as well, going from the Donegal league to the League of Ireland.
“The coaches there, Joe Boyle and Declan Boyle, and the manager Ollie Horan, were all brilliant with me and I can’t thank them enough.”