With the greatest respect mate - they are knackered. You may not like that but it is a fact - hence they were both subbed. They are no spring chickens and they're responsible for most of our assists and goals this season.
I would give Cardiff a freebie because they would beat our best eleven anyway. Just get them out of the league and focus on the play-offs where our toughest possible game would be against a footballing team in Fulham. Get our best eleven fresh and injury-free because those 3 games are now all that matters - sod the rest.
Starting eleven v Cardiff should include Bunn, Bree, Samba? Suliman? Taylor, Whelan, Lansbury, Odomah, Green, Davis etc. I don't familiarise with players on loan but it doesn't matter - just protect our best eleven and keep them for the play-offs.