Flintoff (left) and Pietersen have endured gruelling winters
England's Andrew Flintoff and Kevin Pietersen will be fit for the deciding one-day international against West Indies on Friday following scans.
Pietersen suffered a back spasm bowling in the nine-wicket win in Barbados on Sunday, while Flintoff injured his left thumb attempting a sharp return catch.
Flintoff had an ultra-sound on his thumb after Sunday's win but both players remained in Barbados for tests.
The pair will now join up with the party in St Lucia for Friday's match.
England captain Andrew Strauss, meanwhile, played down suggestions of unrest in the squad caused by Pietersen's comments that he was desperate for the tour to end so he could return to England.
"KP knows it's an England tour and we all stick at it together," said Strauss of his predecessor as skipper.
"He has been nothing but supportive on this tour and very professional with the way he has gone about his business.
"It's not worth dwelling on his comments too much and now we move to St Lucia. It's over, I had a chat with him about it and we move on from there."
We'll go into Friday's game with a lot of confidence knowing we're up and we can beat these guys
West Indies have been forced into one change to their squad after left-arm spinner Nikita Miller was withdrawn with a side strain.
Miller suffered the injury while batting on Sunday and has been replaced by fellow slow left-armer Sulieman Benn.
Victory for England in the fifth ODI would be a welcome fillip for Andrew Strauss's side, who have endured a miserable few months, first in India, then in the Caribbean.
England had not registered a victory before beating the Windies in the opening ODI, but lost the second match by 21 runs before being skittled for 117 in the third en route to an eight-wicket defeat.
However, Strauss hit a blistering 79 not out and Dimitri Mascarenhas took 3-26 as England won the fourth match to set up the rubber.
Hampshire all-rounder Mascarenhas recognises the final match in St Lucia as a big opportunity for England to salvage something from their winter.
"It was a pretty humiliating loss [on Friday], we got absolutely pumped," said Mascarenhas, who was hit for 24 in one over by Chris Gayle.
"It hasn't been the best of winters for the England cricket team as yet, but we've got a really huge chance on Friday to turn that right around and come away with a series win in the West Indies, which would be a great effort.
"We've got four or five days now to get our heads around what's required in the next game.
"There might be different conditions and all those sorts of things are a factor, but we'll go into that game with a lot of confidence knowing we're up and we can beat these guys."