The Ireland assistant coach has praised the quality of the Villa centre back and believes that he is currently the best player in Paul Lambert's team
The 23-year-old defender has been a regular fixture in Paul Lambert's side this season, captaining the team on occasion in the absence of Ron Vlaar, and Tardelli believes that Clark has been performing to a high standard, despite Villa's form.
"I think Ciaran is playing very well," he told reporters ahead of Wednesday's international friendly against Poland. "It's true that Aston Villa concede many goals but a player can change in the national team."
"Now, in this moment, Ciaran Clark is the best player in Aston Villa because they believe in him," he added.
Ireland boss Giovanni Trapattoni has not been able to call upon Richard Dunne, who has been sidelined since Euro 2012, but has included Derby County captain Richard Keogh in his squad for the game against Poland, as well as Reading's Alex Pearce.
Trapattoni's assistant, Tardelli, has praised the ability of Keogh, who is a former Ireland under-21 international, and suggested that they had 'many players' available to compensate for the absence of Dunne.
"Keogh is a good player," said Tardelli. "He is like [Sean] St Ledger, maybe stronger physically, and the head is like Richard Dunne. It's possible that in the future he can play for us."
"We have many players. After the match we will know if we have good options or not," he added.