Alex Sandro said he is ready to go into battle against Serie A scudetto rivals Roma only a week after completing his "dream" move to champions Juventus from FC Porto.

Brazilian defender Sandro was left on the bench for the Turin giants on Sunday when they were stunned 1-0 by Udinese -- the first time Juventus have been beaten at home in a Serie A opener.

The 24-year-old left-back lamented the lapse of concentration which allowed unmarked Frenchman Cyril Thereau to slide the ball past Gianluigi Buffon at the keeper's far post late in the second half and cost Juve their first win of the season.

But Sandro is more than ready to step up to the plate if called into Massimiliano Allegri's starting eleven next weekend when the champions meet bitter rivals Roma at the Stadio Olimpico.

"Yesterday it felt really good being part of the squad at home despite the fact we lost due to a moment's lack of concentration. Apart from that, we played really well," Sandro told reporters in Turin on Monday.

"We meet Roma next week and, like all 'clasicos', it will be a tough game. But if the coach calls me up I'm ready. I've been ready to play for a long time."

Sandro, who was briefly linked with a move to Manchester United last year following the departure, to Juventus, of Patrice Evra -- one of his "idols" along with Roberto Carlos -- ended his four-year spell with FC Porto last week when he signed a five-year contract with the Italian league and Cup champions worth 26m euros ($30 million).

Having won successive league titles with the Portuguese giants in 2012 and 2013, Sandro is relishing the chance to develop his career with Juventus -- who lost to Barcelona in last season's Champions League final.

"It's been my dream to play for Juventus since I was a kid and now it's come true," he added, admitting that he jumped at the chance to join the club when the opportunity arose.

"When Juventus came into the picture, there was no hesitation. It's the perfect choice for me and I believe I can really develop my game here."

Known for his powerful runs, ability to beat opponents one-on-one and his crossing skills, Sandro is seen as a welcome addition to Allegri's side.

"I think right now he's one of the best in Europe in his position," said Allegri.