Mark Warburton signs two former Rangers stars for QPR - reports
Kelly moves for a cut-price fee of £50,000 after triggering a transfer release clause in his contract at Livingston.
The 23-year-old enjoyed a stellar season in the top flight of Scottish football last term and was included in Steve Clarke's first squad as Scotland manager.
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Hide AdWallace, meanwhile, will sign on at Loftus Road after eight years at Ibrox.
The left-back has barely played over the last two seasons. Injury robbed him of the majority of the 2017/18 campaign and he was unsuccessful in his attempts to force his way back into the starting XI under Steven Gerrard last term.