Earlier this week, the 24-year-old singer, the last original member of the group, announced she had been forced to leave. Keisha has now been replaced by Eurovision runner-up Jade Ewen.A source told us: "Keisha has known Ne-Yo for a few years. They are close friends and have worked together on Sugababes material. So when he heard she had left the group he contacted her and told her he wants to work with her. Keisha is also good friends with Jermaine Riley from FDM, who is signed to Ne-Yo's label. When he heard of the split he told her to call him as he had some big news."