Clermont Auvergne's medical staff had been tipping that Jones would make a stunning recovery from an ankle injury suffered against Biarritz last weekend. He was included in the initial squad of 24 named to play Stade Francais Paris on Saturday, but didn't make the final cut.
'It's a pity I couldn't play, because we've got an incredible crowd in, the weather's perfect and these are the sorts of games everyone wants to play,' Jones said. 'I believe I could have played, but there are still a few doubts about the ankle. The only wish you have when you're injured is to get back playing as quickly as possible.
'I really thought I would be fit for this game, but it's obviously going to take a few more days.'
A Clermont club spokesman said Jones's ankle would be looked at on Wednesday, in the hope of playing him against Castres next weekend. The delay in his return is another setback for Wales coach Ruddock, who is spending more time looking at X-rays than training videos these days.
World-class prop Gethin Jenkins (shoulder) and gifted centre Gavin Henson (groin) have already been ruled out of the autumn internationals. Scrum-half Dwayne Peel will have an ankle operation on Monday and will out of action for at least a fortnight, although understudy Gareth Cooper started on the bench for the Dragons on Saturday night.
Centre Tom Shanklin (knee) came through the Blues' loss to Wasps on Friday night unscathed, while Lions backrower Ryan Jones (shoulder) returns for the Ospreys against Bath on Sunday.
Ruddock's biggest problem next month could be at hooker. Robin McBryde has retired from rugby because of on-going neck problems, while possible replacements Rhys Thomas, Matthew Rees and Gareth Williams are all twiddling their thumbs on the injury list.
On the good-news front, Scarlets backrower Dafydd Jones (finger) is making a faster-than-expected recovery and may be available for the autumn Tests, and captain Gareth Thomas's sore shoulder is not considered a problem.
The WRU has launched a campaign to create a long term legacy for Welsh club rugby by highlighting the advantages of volunteering. Rhian Edwards, a volunteer at Seven Sisters, has enjoyed many benefits of her volunteering at a grassroots rugby club including being part of the Rugby World Cup volunteer workforce after being nominated by the WRU - and the WRU is asking for more people to develop their 'Welsh rugby roots'.
Wales head coach Warren Gatland and captain Sam Warburton say their first prioirty on Sunday in the opening game of the World Cup is to win against Uruguay and not get overly concerned with points difference.
With only days to go until the biggest rugby competition in the world begins, rugby fans visiting Cardiff this autumn will be able to enjoy a special display at National Museum Cardiff as part of the celebrations surrounding the Rugby World Cup.
Geraint John has taken up the new role of WRU elite coach development manager having arrived in Wales last week. WRU TV caught up with him at the WRU rugby department's strategy day at the Millennium Stadium.