Italian Dario Cataldo will leave Team Sky next season for team Astana, where he is on contract for one year with the Kazakh squad.
"Dario is a very important signing for Astana," general manager, Alexandre Vinokourov said, "and will be a great addition to the team."
"He will be a great gregario for Aru as well as Nibali, and plus, he knows the ins and outs of doing a good TTT," Vinokourov added. "Make no mistake, Dario Cataldo is a very important addition for the team."
The 29-year-old from Abruzzo spent the last two years, 2013 and 2014, with Sky and rode alongside Bradley Wiggins in the 2013 Giro d'Italia. This March, he won the Coppi & Bartali time trial and helped Peter Kennaugh win the overall in the Italian stage race.
Prior to joining Sky, he raced for Omega Pharma and Liquigas. In 2012, he won a mountain stage of the Vuelta a España and twice finished 12th overall in the Giro d'Italia.
With Astana, he will likely help 2014 Tour de France winner Vincenzo Nibali and rising star Fabio Aru, both Italians.
Astana has already signed Davide Malacarne, Rein Taaramäe, Laurens de Vreese, Luis Leon Sanchez, Lars Boom, Diego Rosa and Miguel Ángel López for 2015.
Sky has welcomed Andrew Fenn, Leopold König, Wout Poels, Lars Petter Nordhaug and Nicolas Roche.
In addition to Cataldo, Edvald Boasson Hagen is leaving to join MTN-Qhubeka.
The British team has yet to announce if it is resigning some riders, including Joe Dombrowski and Wiggins. Wiggins is expected to stay, but Dombrowski is said to be leaving to team Cannondale.
