Habib Beye believes Newcastle need two wins and a draw from their last three games to avoid relegation from the Premier League.
The Magpies are currently three points adrift of safety ahead of Monday night's encounter with North East rivals and fellow strugglers Middlesbrough.
They go on to face Fulham in another home game next weekend before travelling to Aston Villa on the final day of the season.
Beye accepts that another defeat would consign Newcastle to the Championship, saying: "We know what we need to do.
"I think we need to get seven points to stay in the Premier League.
"We can't afford to lose any more - we just need three points on Monday."
The clash with Boro has been billed as the club's biggest game for many years and Beye admits it is one that Newcastle must win.
He said: "We need to focus on the game against Boro. It will be the most important game for everybody in their lives.
"We have three games left now, and I think everybody knows what we need to stay in the Premier League."