Amakhosi are scheduled to host the Buccaneers in the 2019 Telkom Knockout Cup quarter-final match at Moses Mabhida Stadium on Saturday.
In-form full-back Reeve Frosler and midfield maestro Kearyn Baccus will miss the highly-anticipated clash due to injuries.
“It looks like Reeve Frosler will probably not be available," Middendorp told the media.
"Kearyn Baccus will definitely not (play), but we said it immediately after his injury that he will take a time of three weeks.
"At the moment we’re in the second week, so we’re saying no chance," he continued.
Middendorp is expected to look to defender Siyabonga Ngezana and central midfielder George Maluleka in the absence of the two injured players.
“Otherwise, good, we have experienced the substitutions coming in," the former Asante Kokoto head coach added.
"So far, we are busy preparing players to take over these positions, hopefully with the same performance as we have seen lately.”
Chiefs will be looking to reach the Telkom Knockout semi-finals for the third year running when they lock horns with Pirates.
They were eliminated in the semi-finals by Bidvest Wits and Pirates in the last two competitions.