Claudio Marchisio has labelled defeats in the 2015 Champions League and Euro 2012 finals as the biggest regrets of his career.

Former Juventus stalwart Marchisio confirmed his retirement on Thursday, having been without a club since Zenit agreed to mutually terminate his contract in July.

The 33-year-old had been plagued with injuries in the latter stage of his career, but he was a key cog in Juve's era of Serie A dominance.

In total, Marchisio won 15 trophies, including seven Serie A titles, during his time with Juve, having come through the club's academy.

Marchisio twice featured in the Champions League final – in 2015 and in 2017 – but on both occasions Juve were beaten, first by Barcelona and then Real Madrid.

He also made 55 appearances for Italy, helping them to the final of Euro 2012, in which they suffered a 4-0 defeat to Vicente del Bosque's all-conquering Spain side.

"Let's speak about regrets. In the whole Juventus winning cycle, for sure the regret is the 2015 Champions League final and the 2012 Euros with Italy," Marchisio told a news conference.

"Two moments that, despite a winning spell, [that] they don't appear in my trophy cabinet it is the biggest regret."

Alvaro Morata hauled Juve level against Barca in Berlin in 2015, only for Luis Suarez to nudge the Catalan giants back ahead before Neymar wrapped up a 3-1 triumph late on.

"I wish I could re-play the Champions League final in Berlin," Marchisio added.

"It was a battle with the result we all know. If only we could re-stage it, not even in its entirety, just a part in the second half to score before them."

Marchisio left Juve in 2018 but insists he will never lose his love for the club, although he acknowledged the eight-time defending Serie A champions face a real challenge from Inter this season.

Antonio Conte has rejuvenated Inter since taking over and faces his former club on Sunday, with Marchisio paying tribute to a coach he worked under with both Juve and Italy.

"Inter started very well, getting results and Juventus, at the moment, are behind and have to chase," he said. "It will be a great match. I will watch it as a Juventus fan, and I can't wait to see Juventus win.

"[Inter] are almost the same [in terms of personnel] as last year but are showing a completely different approach and team spirit. That is Conte's hand!"