Red Bulls coach Marsch described Carnell as a highly experienced coach, having spent most of his playing career in Germany.
“Bradley brings a tremendous amount of experience from his time playing at high levels in Germany and with his national team,” Marsch told the club’s website.
“We look forward to him bringing that perspective to our staff and helping us prepare our team each week.”
Carnell worked alongside Italian coach Giovanni Solinas at Ea Lla Koto and went on to join Pirates where he worked with Muhsin Ertugral, before leaving his post in February.
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