Middlesbrough manager Aitor Karanka has praised his side's strength in depth following their 2-1 victory over Sunderland.
Boro made it four points from their two games since returning to the Premier League by beating their North-East rivals, with Cristhian Stuani getting both goals at the Stadium of Light.
The Uruguayan was not in Middlesbrough's starting lineup for their opener against Stoke City, and Karanka believes that that is proof of the quality he has throughout his squad.
"Cristhian comes in for his first start and gets two great goals, but it's a squad game and we have got strength in depth now. We have got two players in nearly every position, so you have got to be on your toes and play well," he told reporters.
"Everyone is fighting. It's obviously disappointing when they don't play - everyone is like that - but it's a team game and players will be needed over the course of the season."
Boro will face Fulham in the EFL Cup on Wednesday before taking on West Bromwich Albion in their next Premier League game.