Juventus midfielder Hernanes has promised to "show his strength" and respond positively to criticism he received after Saturday's defeat to Napoli.

The Brazilian arrived at Juventus Stadium following an 11 million euro ($12.3 million) transfer from Inter but has struggled to settle into a deeper midfield role in recent weeks.

After his error was directly seized upon by Gonzalo Higuain to score Napoli's second goal in a 2-1 win over the defending Serie A champion, Juve coach Massimiliano Allegri quickly substituted him.

However, in a show of defiance, the midfielder insisted he will come through the turbulent spell together with his teammates.

"I worked so hard to get into a team like Juventus, I have not given up a centimetre by reaching this goal," Hernanes posted on his Instagram profile. "The other night the game went wrong and we are sorry for this. But I will show all my strength and I will honour this shirt and these colours together with my teammates."

After a dismal start to the new campaign Juventus occupy 15th position in the Italian top flight, just two points clear of the relegation zone.