The 24-year-old Merthyr-born second row has signed a two-year deal with the Arms Park club – a move which is likely to lead to fellow Welsh internationals Gethin Jenkins and Deiniol Jones following suit.
With WRU boss David Moffett opting to shut down the Warriors after only one season by putting the new region into liquidation this week, Sidoli was one of many players looking to secure his future.
Zurich Premiership side Sale Sharks and a host of leading French clubs, including big spending Perpignan, expressed interest in his considerable talents, but the Blues have won the race for his signature.
“We were all gutted by what happened to the Warriors, but the main thing for all of us has been to put it behind us and secure our futures,” said Sidoli.
“When we heard what was happening to the Warriors I said that I wanted to remain in Wales.”
Sidoli is missing out on this month’s three-Test tour to Argentina and South Africa after having surgery on a long standing pelvic problem last week. Hi splace has been taken by his younger brother Peter, who plays for the Dragons.
“The operation went very well and I expect to be back in training in three or four weeks time. I want to have a good pre-season in order to make up for missing out on the tour,” he added.
The formal announcement of his signing will be made by the Blues later this week and comes hot on the heels of the Dragons snapping up ex-Warriors Gareth Cooper, Ceri Sweeney, Jon Bryant, Gareth Wyatt and Richard Bryan and the Ospreys signing Brett Cockbain, Ryan Jones and David Bishop.
Tongan wing Aiesa Havili and hooker Matthew Rees have joined the Scarlets and prop Chris Horsman has gone back to England to play for newly promoted Worcester.
Wales centre Sonny Parker and hooker Mefin Davies are the two big name Warriors still without a new club.
