Fulham’s win at Liverpool on Saturday afternoon drew them level on points with Graham Potter’s side, though have played a game extra.
The joint tally is 26, while Newcastle sit one position higher on 27 points, who have won just two of their previous 18 matches in all competitions.
Plenty of praise has been heaped on Potter and his attractive style of play but Albion’s struggle to score goals has led them deep into relegation trouble.
However, Sinclair, appearing as a pundit on talkSPORT, has urged Potter to keep the faith in his “principles and philosophy”.
Indeed, he believes it will be enough to keep the club in the Premier League, with Newcastle tipped as the team to claim the final relegation spot.
When asked who would join the bottom two Sheffield United and West Brom in the Championship next season, Sinclair said: “Unfortunately, I think it is going to be Newcastle.
"They miss Callum Wilson hugely. I don’t know what the exact percentage is but he scores most of their goals. If he’s not in the team, I don’t see them winning enough games.
"Graham Potter – why would he change his principles? Why would he change his philosophy? They are playing great football.
"It’s the final piece of the jigsaw and the most important part most of the time is putting the ball in the back of the net.
"You can’t change your principles and philosophy of how you play and the performances you’re putting in just because you’re not scoring goals.
"Stick to it. Keep practising and you’ll turn it around.