The squad is littered with injuries and the United boss will leave team selection until the last possible moment.
Midfield duo Seth Johnson and Jody Morris are Reid's biggest worries with the pairing struggling with knee injuries.
Morris came off against Southampton in midweek while Johnson's problem is ongoing and the player suffers swelling on his knee after games.
Skipper Dominic Matteo is also struggling with an ankle problem, but Lucas Radebe should be fit again after missing the Saints clash.
Ian Harte has shaken off a knee problem, but Didier Domi is pushing for a place in the squad after completing 90 minutes in the reserves on Wednesday.
Reid said to the Yorkshire Evening Post: "We've got a few knocks and I'll be leaving it as late as possible before assessing where we are."
United have a two-week international break after the trip to The Riverside and Reid is looking for his men to enter the this period with a first win of the season.
United have played well in the opening weeks, but have lacked the killer touch to turn performances into points.
"I'm as disappointed as anyone that we haven't won yet," said Reid.
"I feel for the players because they have given their all and we deserve more points than we have.
"It's just a case of turning the performances into results, because I think we're getting there."
The United players were down after losing to Tottenham last Saturday and were gutted not to pick up all three points against Southampton in midweek.
"The lads are positive and we'll got to Middlesbrough full of confidence," said Reid. "We need to go do it at Boro because a win will give everyone an even bigger lift.
"I'm pleased with how things have gone because we kept a clean sheet against Southampton and the two goals we conceded at Tottenham were great strikes, although the second one was offside."
Leeds from: Robinson, Kelly, Camara, Radebe, Matteo, Harte, Pennant, Morris, Johnson, Batty, Sakho, Viduka, Smith, Martyn, Lennon, Milner, Wilcox, Barmby, Domi.