Mettenberger said that O'Brien is a "football genius" and has enjoyed every time that they have interacted throughout the pre-Draft process.
"[The meetings have] been good, I think," Mettenberger told the club's official website.
"Coach O'Brien is a great guy. He's a football genius, and someone that I'd really like to work with. Every interaction I've had with him so far has been great."
Mettenberger is currently carrying an injury, but expects to be fit for the training camps next month.