Coach Olexiy Mykhaylychenko said Voronin was less than 100 percent fit, without giving precise details, while local media have reported a rift between the pair.
Ukraine are second in Group Six behind already-qualified England, knowing a victory against bottom team Andorra will clinch a place in next month's two-legged playoffs.
If Mykhaylychenko's team fail to win, Croatia can pip them for second place with a victory in Kazakhstan who are second from bottom.
"Andorra are not the weakest opponents," Mykhaylychenko told reporters after Saturday's 1-0 home win over England.
"The Croats had problems playing in Andorra and England only managed to crack their defence in the second half. We need to take one more step but it will not be easier than the game against England."
After a lacklustre goalless draw against Belarus last month, Ukraine's chances of qualifying seemed on the wane.
However, the victory over England has put them right back on track.
The visitors had goalkeeper Robert Green sent off early in the game and Ukraine took advantage when Sergiy Nazarenko grabbed the only goal later in the first half.
Ukraine could even afford the luxury of a missed penalty by talismanic striker Andriy Shevchenko.
"Believe In Wonders" and "Long Live Ukraine" were some of the headlines that appeared in the local media on Sunday.
