The left-back, who celebrated his 29th birthday on Monday, has been left frustrated at the club's plight of late as the encouraging first month in the top flight following last season's promotion from the Championship has since turned sour.
Boro picked up five points from their opening three matches in August, but have managed just one point from the following five games which has left them outside of the relegation places only on goal difference.
Some fans made their feelings known following Sunday's dismal 1-0 defeat against Watford at the Riverside Stadium, but Friend is urging them to rally behind the team and help them recapture their form.
Friend, who has been wearing the captain's armband in the absence of the injured Grant Leadbitter, said: "It's the Premier League, and we all know it's hard. We started off very well, but we’ve got to stay positive, and I know we will.
"That's as a collective, and by collective I mean the fans, the staff, the team, everyone. The spirit of Teesside that got us up last season is going to keep us up as well.
"My message to the fans is don’t get nervous, don't get negative. It's about staying positive - that goes for everyone because we need to pick up points.
"It's about Boro, because when the team does well, the area does well, so let's all stay positive and enjoy it."