Burnley without trio for return to Premier League action at Southampton
Brady was forced off midway through the first half of the Republic of Ireland's 1-1 draw with World Cup hosts Qatar on Tuesday night, with the Achilles problem which troubled him in February.
He is expected to be out for "a few weeks at least" according to boss Sean Dyche - with the former record signing's future in doubt with his contract set to run out in the summer.
Striker Barnes is still struggling with a thigh problem, while Long has a calf injury which forced him to pull out of the Ireland squad before the first of their three games over the international fortnight, against Serbia.
Dyche said: "Robbie Brady came off and is definitely not going to make it.
"We are waiting on the results of scans and stuff as to how long that is going to be.
"It looks as though one that will keep him out a few weeks at least.
"Barnesy is making good progress but he is not quite there yet, but he is coming through his training programme so we are hopeful that will be sooner rather than later, but he will need a bit of training with the players.
"And Longy has a calf (injury). He is unlikely for this weekend, not too serious but unlikely for this weekend."
However, Charlie Taylor and Jack Cork return to the thinking, with both having trained during the international fortnight: "They've been in full training and getting stronger - still ideally need more, but they are available."