The Uzbeks defeated China on penalties in the quarter-finals but were reduced to 10 men in the final minute of extra time when Usmonov was dismissed for seemingly putting his hands on referee Benjamin Williams.
"We are going to miss Doniyorjon Usmonov, who was sent off in the previous game, but our reserve goalkeeper Ilhom Djumanov is ready and he will replace him," Ubaydullaev said.
"We will also miss Davron Mirzaev, who hasn’t recovered from injury."
Ubaydullaev knows the size of the task his side face against a Korean team that brushed aside last year’s runners-up Japan 3-0 in the last eight if they are to reach the final but insisted they will give it their all.
"Our opponents are very strong, especially as they defeated Japan in the quarter-finals," he added.
"They have a good side and they have a lot of strong points.
"They almost don’t have any weaknesses while they have talented players.
"They are good at playing both long and short, while the speed of their players could cause a lot of problems for us.
"It could be hard but we will fight until the end of the game. We have a good side and we want to continue winning in the tournament and hopefully we can qualify to the final."
Korea Republic coach Cho Dong-hyun admitted he will employ a more defensive approach against the Uzbeks.
"I didn’t see Uzbekistan’s previous match, I only had a chance to see it on video," said Cho.
"Uzbekistan are very strong offensively and we will stress a defensive strategy in the game.
"It will be hard to say who is going to win. I can’t say that I’m confident that we will qualify to the final but all I can say is that we will do our best in the game against Uzbekistan and hopefully we can win."
Cho is also hopeful Korea will prove more clinical in front of goal against the Central Asians.
"We had some problems in attack against Japan as we had a lot of chances to score," he added.
"We have worked on this problem in the training and hopefully this aspect will improve against Uzbekistan.
"We don’t look at previous results between Uzbekistan and Korea Republic because they are in the past.
"The important thing will be to focus on the match and we are eager to win the game."