A Football Association of Wales spokesman said yesterday that the Leicester City midfielder was injured in the 1-0 win over Watford on Monday and was ruled out after a medical at the team hotel. Jones, 19 yesterday, was promoted from the Under-21 party.
For their part, Belarus will be without five key players for the match due to injury or suspension.
The two teams occupy the last two positions in Group One and although Wales retain a slim mathematical chance of finishing second in the group, both are playing for little more than pride. Wales beat Belarus 3-2 at home when they met last October.
Similarly, Northern Ireland have little to play for against Turkey in their Group Three qualifier in Belfast on Saturday. The Ulstermen trail the joint leaders in the section, Germany and Turkey, by six points.
At least Northern Ireland have no injury worries, and their manager, Lawrie McMenemy, said that Peter Kennedy, who has a slight hip problem, and Stephen Robinson (shoulder) will be available. The Wimbledon winger Michael Hughes is expected to partner the 34-year-old Iain Dowie in attack.
Northern Ireland will wear black armbands and there will be a minute's silence before Saturday's game in memory of the victims of the Turkish earthquake.