Cole's arrival at the Stadium of Light on a one-year deal will see the 35-year-old revive one of the most famous double acts in English football with Dwight Yorke.
The pair scored almost 60 goals between them during Manchester United's treble winning season in 1998/9 and Murphy also feels Yorke has a big role to play as Sunderland attempt to consolidate their place in the Premier League.
He said: "I wouldn't say it's strange having big-name players around because why shouldn't we be attracting those sort of players to the club? We've had Yorkie for a while now and his experience shows. It's good that players of that stature come in.
"Dwight helps everyone. The experience he has is unbelievable and as a former striker he's brilliant to have around. He helps us out in shooting exercises and stuff like that. He tells us where we should be position-wise and things like that."