
Management at the Ukrainian side appointed assistant coach Oleg Luzhny to the top job late Sunday evening, after his predecessor Josef Szabo bowed out citing heart problems.
Kiev face United at Old Trafford in a Group F match on Wednesday.
Szabo had taken over Dynamo in September, in the midst of the side's worst season start in a decade.
Historically Ukraine's strongest football team and during the 1970s and 80s one of the most feared sides in Europe, Dynamo have lost all three of their Group F games so far, including a 4-2 defeat to United in Kiev last month.
Luzhny made clear he was only a caretaker in the head coach job, and conceded his work would be cut out ahead of the match against Manchester United.
"I am only temporary, and we have only three days to prepare," Luzhny said in a statement.
"Of course I hope our players will do their best and our team will succeed ... but we can only do the best we can."
United go into the match coming off of a draw Saturday at Arsenal, with the Gunners scoring an equalizer in injury time.
Normally dominant in Ukraine's domestic league, Dynamo are currently joint third. Dynamo are a perennial Champions League participant but, if present Ukraine league standings hold out, they would fail even to qualify for next season's competition.
Dynamo president Ihor Surkis in an interview with Sehodnia newspaper hinted broadly club managers had given up even the hope of a third place in Group F.
"We only have to get through the next eight (domestic and Champions League) matches before the winter break, and then there will be a purge," he warned.
"We (Dynamo management) know what we need to do, and we are ready to take steps ... we are even prepared not to compete in Europe at all next year, in order to build a new team."
Surkis compared Dynamo's upcoming transition to the recent overhaul and massive cash injection by Germany's Bayern Munich.
"Bayer went down this path only recently, and it will not be shameful for us to follow in their steps," he said.
Surkis's comments were the most open public admission yet that the club's traditional policy of trying to build a team using training techniques and staff developed by legendary coach Valery Lobanovsky during the team's glory days prior to the break-up of the Soviet Union, will this winter be finally abandoned.
"We can no longer afford to live in the past, we must move forward," Surkis said. "And to do that we will have to overhaul almost every aspect of our organisation."
Surkis said Dynamo's next coach "almost certainly" would not be a former player of the side, and in an even more dramatic break with club tradition warned that other functionaries not pulling their weight would be sacked, even if they had once been Dynamo's greatest footballing stars.
"Many people (on the staff) want to get a result without much effort," Surkis said. "Things do not work that way."
Surkis named as other upcoming priorities in the upcoming shake-up the jettison of up to half of the side's foreign players, the replacement of senior Ukrainian players by a new generation in their late teens and 20s, and the removal of excess support staff through voluntary retirement or sacking as the main priorities in the planned overhaul.
"This winter, there will big changes in the club," Surkis said. "We are waiting for winter like manna from heaven."
DPA