Giorgio Chiellini exit down to 'muscular fatigue' - Massimiliano Allegri

Juventus boss Massimiliano Allegri did not appear overly concerned about Giorgio Chiellini's injury, despite seeing the key defender forced to leave the pitch late-on in Saturday's 0-0 stalemate with SPAL.

The 33-year-old Italy international was substituted in the 81st minute and is now in doubt for the Azzurri's upcoming friendlies against Argentina and England.

"Chiellini has muscular fatigue, but at the moment we don't have any more on that," Allegri said after the match.

"It's only human that when you are top of the Serie A table, in the Champions League quarterfinals and the Coppa Italia final, you can miss a beat and lack energy once in a while."

Allegri's side missed out on extending their lead at the top of the Serie A table to seven points, with Napoli set to close the gap to two should they beat Genoa on Sunday.

"People expected us to drop points a couple of weeks ago against Lazio. We dropped them tonight. These things happen," Allegri said.

"Now we need some rest, because we are playing on three fronts and we need everyone."