Scrum half Leadbeater, who has come through the Dragons Academy and represented Wales at Under 20 level will start on the bench as both Wayne Evans (knee) and Alex Walker (shoulder) are ruled out with injury.
Dragons back row Gavin Thomas will start to get his 50th Heineken Cup cap and hooker Steve Jones is set to captain the side.
Rob Sidoli who came in to the away leg to replace the injured Luke Charteris (thigh) is joined by Hoani Macdonald and Martyn Thomas comes in for the injured Jason Tovey (ankle)
“Our injuries are a big blow,” said Dragons Head Coach Paul Turner. “Luke Charteris and Dan Lydiate are our in-form Welsh players at the moment and it’s very disappointing for them and for the team as a whole that they can’t be involved tonight. This is offset to a certain extent by the return of Tom Willis and Joe Bearman whose absence has been really felt on the pitch.
“There is no doubt that we need a win tonight to keep our European hopes alive. We need to start well and eradicate the errors from last weekend. A week (or should I say five days) is a long time in rugby and tonight we are certainly looking to set right the problems of last week and take the game to Biarritz.”
Dragons Martyn Thomas, Aled Brew, Thomas Riley, Mathew Watkins, Richard Fussell; James Arlidge; Danny Lee; Alistair Mckenzie, Steve Jones (C), Peter Bracken, Hoani Macdonald, Robert Sidoli, Joe Bearman, Gavin Thomas, Grant Webb
Replacements Tom Willis, Hugh Gustafson, Gethin Robinson, Lewis Evans, James Harris , James Leadbeater, Shaun Connor, Rhodri Gomer Davies
