MILAN (Reuters) - Juventus have signed Lazio defender Guglielmo Stendardo on loan for the rest of the season while Aston Villa's Olof Mellberg will join in July, the Serie A club said on Monday.

Claudio Ranieri's side are also expected to seal Mohamed Sissoko's transfer from Liverpool later before the Mali midfielder heads back to the African Nations Cup in Ghana.

Third-placed Juve have a defensive injury crisis and have brought in Italian Stendardo after a move to recruit Sweden's Mellberg in January stalled.

Villa blocked an early deal but his contract runs out in June and the 30-year-old will be a Juve player for next season having penned a three-year deal, a Juventus statement said.

"I am very happy with this agreement. Italy will be an important experience, at a prestigious club and in one of the most important championships in the world," Mellberg said.

"Now I must finish the season in an Aston Villa shirt but I really can not wait to come to Juventus."

Stendardo's move, signalled on the Italian club's Web site (www.juventus.com), comes despite the defender being in the middle of a three-match league suspension.

Lazio have replaced him by signing Dinamo Bucharest's Stefan Radu on loan for the rest of the season, the Romanian club's vice president Vasile Turcu told Realitatea television.

Lazio were unavailable to confirm the deal but Turcu said the struggling Rome club would be able to sign the Romania defender permanently after the loan spell.

(Editing by Justin Palmer)