Arrigo Sacchi has defended Italy coach Marcello Lippi's decision to continue to leave Sampdoria forward Antonio Cassano out of his squad.

Lacklustre performances by the world champions this summer have led to calls for Lippi to recall Cassano to the national side.

"Cassano? Football is a complex matter," the former AC Milan boss told Italian Radio Kiss Kiss. "It has 11 uncertainties, not just one.

"Perhaps Lippi doesn't call up Cassano because he doesn't give him enough guarantees or because he is convinced that he is a lone striker and would not fit in with his tactics."

The Azzurri have struggled in front of goal in their last four matches and won 2-0 at Georgia in Saturday's World Cup qualifier thanks to two own goals by AC Milan defender Kakha Kaladze.

Cassano was in Roberto Donadoni's Euro 2008 squad but ever since Lippi returned as coach, the striker has not featured for the Azzurri.

The former Roma and Real Madrid forward has had a reputation as something of a troublemaker, but has matured in his two seasons at Sampdoria.

Sacchi, who guided Italy from 1991 until 1996, believes Lippi, a World Cup winner and one of the most successful Serie A coaches of all time, knows what he is doing.

"Lippi is an experienced coach," he said. "He tries to select players that are the most reliable and who can give him the best."

Italy go into Wednesday's World Cup qualifier against Bulgaria in Turin leading Group Eight with a one-point advantage over Ireland and a game in hand.